Wednesday, December 17, 2014
Home Diseases & Conditions
Eye Allergy (Allergic Eye Disease) - Food Allergy

Eye Allergy
(Allergic Eye Disease)

 

View the Eye Diseases and Conditions Slideshow Pictures

 

 

 

 

Eye Diseases and Conditions Slideshow Pictures Eye Diseases and Conditions Slideshow Pictures
Pink Eye Slideshow Pictures Pink Eye Slideshow Pictures
Cataracts Slideshow Pictures Cataracts Slideshow Pictures

 

  • Eye allergy introduction
  • What is the basic anatomy of the outer eye?
  • Why are the eyes an easy target for allergies?
  • What are allergic eye conditions?
  • What are eyelid allergies (also called contact eye allergies)?
  • What conditions can be confused with eye allergies?
  • How do we care for allergic eyes?
  • Eye Allergy At A Glance
  • Patient Discussions: Eye Allergy
  • Find a local Asthma & Allergy Specialist in your town

Eye allergy introduction

Picture of eye allergies

The eyes are the windows to the soul because they reflect our state of mind. This certainly can't be true if our eyes are red, swollen, watery, and itchy from an allergic reaction. Severe allergic eye symptoms can be very distressing and are a common reason for visits to the allergist, ophthalmologist, and even the emergency room. Occasionally, severe eye allergies cause serious damage that can threaten eyesight.

Eye allergies usually are associated with other allergic conditions, particularly hay fever (allergic rhinitis) and atopic eczema (dermatitis). The causes of eye allergies are similar to those of allergic asthma and hay fever. Medications and cosmetics can play a significant role in causing eye allergies. Reactions to eye irritants and other eye conditions (for example, infections such as pinkeye) are often confused with eye allergy.

What is the basic anatomy of the outer eye?

Eye allergies mainly involve the conjunctiva, which is the tissue lining (mucus membrane) that covers the white surface of the eyeball and the inner folds of the eyelids. The conjunctiva is a barrier structure that is exposed to the environment and the many different allergens (substances that stimulate an allergic response) that become airborne. It is rich in blood vessels and contains more mast cells (histamine-releasing cells) than the lungs.

The lacrimal (tear) glands are located in the upper and outer portions of the eye. They are responsible for producing the watery component of tears, which keeps the eye moist and washes away irritants. The tears also contain important components of the immune defense such as immunoglobulin (antibodies), lymphocytes (specialized white blood cells), and enzymes.

The cornea is the transparent sheath in front of the lens of the eye. The cornea has no blood vessels and very little immune activity.

Why are the eyes an easy target for allergies?

When you open your eyes, the conjunctiva becomes directly exposed to the environment without the help of a filtering system such as the cilia, the hairs commonly found in the nose.

Allergy fact

Approximately 54 million people, about 20% of the U.S. population, have allergies. Almost half of these people have allergic eye disease.

People who are more susceptible to allergic eye disease are those with a history of allergic rhinitis and atopic dermatitis and those with a strong family and/or personal history of allergy. Symptoms usually appear before the age of 30.

The scenario for developing allergy symptoms is much the same for the eyes as that for the nose. Allergens cause the allergy antibody IgE to coat numerous mast cells in the conjunctiva. Upon reexposure to the allergen, the mast cell is prompted to release histamine and other mediators. The result is itching, burning, and runny eyes that become red and irritated due to inflammation, which results in congestion. The eyelids may swell, even to the point of closing altogether. Sometimes, the conjunctiva swells with fluid and protrudes from the surface of the eye, resembling a "hive" on the eye. These reactions may also induce light sensitivity. Typically, both eyes are affected by an allergic reaction. Occasionally, only one eye is involved, particularly when only one eye is rubbed with an allergen, as this causes mast cells to release more histamine.

Allergic conjunctivitis is inflammation of the conjunctiva that is caused by a reaction to allergens. The inflammation causes enlargement of the blood vessels in the conjunctiva ("congestion"), resulting in a red or bloodshot appearance of the eyes.

What are allergic eye conditions?

Allergic conjunctivitis

Allergic conjunctivitis, also called "allergic rhinoconjunctivitis," is the most common allergic eye disorder. The condition is usually seasonal and is associated with hay fever. The main cause is pollens, although indoor allergens such as dust mites, molds, and dander from household pets such as cats and dogs may affect the eyes year-round. Typical complaints include itching, redness, tearing, burning, watery discharge, and eyelid swelling. To a large degree, the acute (initial) symptoms appear related to histamine release.

The treatments of choice are topical antihistamine drops such as olopatadine (Patanol), decongestants, and the newer mast-cell stabilizer medications. Topical steroids should be used only if prescribed by a doctor for severe reactions and on a short-term basis because of the potential for side effects. In general, oral antihistamines like loratadine (Claritin) or cetirizine (Zyrtec) are the least effective option, but they are often used for treating allergic rhinitis together with allergic conjunctivitis.

 

Allergy assist

Rubbing itchy eyes is a natural response. However, rubbing usually worsens the allergic reaction due to the physical impact on the mast cells, which causes them to release more mediators of the immune response. Translation: Do not rub your eyes!

Conjunctivitis with atopic dermatitis

Commonly called "atopic keratoconjunctivitis," this condition is a notorious cause of severe eye changes, particularly in young adults. Atopic keratoconjunctivitis implies inflammation of both the conjunctiva and cornea. "Kerato" means pertaining to the cornea. This form of conjunctivitis usually affects adolescent boys (three times more frequently than girls) and is more common in those who had atopic dermatitis in early childhood. The condition is characterized by intensely itchy, red areas that appear on the eyelids. A heavy discharge from the eyes can occur, and the skin of the eyelid may show scales and crusts. In severe cases, the eyes become sensitive to light, and the eyelids noticeably thicken. If managed poorly, there can be permanent scarring of the cornea due to chronic rubbing and scratching of the eyes. This scarring can cause visual changes.

The triggers for atopic keratoconjunctivitis appear to be similar to those of atopic dermatitis. A search for common food allergies, such as eggs, peanuts, milk, soy, wheat, or fish is important. Airborne allergens, particularly dust mites and pet dander, have been overlooked as a significant contributing factor and should be evaluated and controlled.

The hallmark of treatment for allergic conjunctivitis is the use of potent antihistamines (similar to those used in atopic dermatitis) to subdue the itching. Topical antihistamines, mast-cell stabilizers, and the short-term use of oral steroids are all beneficial for relief of the itching. Occasionally, an infection of the area (usually with staphylococcus, commonly referred to as "staph") worsens the symptoms, and antibiotic treatment may help control the itching. Allergy shots are useful in selected cases.

Allergy alert

Atopic keratoconjunctivitis can lead to cataract formation in up to 10% of cases. In rare cases, blindness can occur.

Vernal keratoconjunctivitis

Vernal keratoconjunctivitis is an uncommon condition that tends to occur in preadolescent boys (3:1 male to female ratio) and is usually outgrown during the late teens or early adulthood. (Vernal is another term for "spring.") Vernal keratoconjunctivitis usually appears in the late spring and particularly occurs in rural areas where dry, dusty, windy, and warm conditions prevail. The eyes become intensely itchy, sensitive to light, and the lids feel uncomfortable and droopy. The eyes produce a "stringy" discharge and, when examined, the surface under the upper eyelids appears "cobblestoned." A closer examination of the eye reveals severe inflammation due to the vast number of mast cells and accumulated eosinophils, producing so-called called "Trantas dots."

Improper treatment of vernal keratoconjunctivitis can lead to permanent visual impairment. The most effective treatment appears to be a short-term course of low-dose topical steroids. Topical mast-cell stabilizers and topical antihistamines can also be beneficial. Wraparound sunglasses are helpful to protect the eyes against wind and dust.

Allergy fact

Keratitis, or the inflammation of the cornea, in vernal and atopic keratoconjunctivitis is largely caused by a substance that is released from the eosinophils, called major basic protein.

Giant papillary conjunctivitis (GPC)

This condition is named for its typical feature, large papillae, or bumps, on the conjunctiva under the upper eyelid. These bumps are likely the result of irritation from a foreign substance, such as contact lenses. Hard, soft, and rigid gas-permeable lenses are all associated with the condition. The reaction is possibly linked to the protein buildup on the contact lens surface. This condition is believed, in part, to be due to an allergic reaction to either the contact lens itself, protein deposits on the contact lens, or the preservative in the solution for the contact lenses. Redness and itching of the eye develop, along with a thick discharge.

Allergy to contact lenses is most common among wearers of hard contact lenses and is least common among those who use disposable lenses, especially the one-day or one-week types. Sleeping with the contact lenses on greatly increases the risk of developing GPC.

The most effective treatment is to stop wearing the contact lenses. Occasionally, changing the type of lens in addition to more frequent cleaning or using disposable daily wear lenses will prevent the condition from recurring.

The giant papillae on the conjunctiva, which are characteristic of GPC, however, may persist for months despite these measures. Eye medications, such as cromolyn (Opticrom) or lodoxamide (Alomide), often are used in this condition, sometimes for several months. Contact lenses should not be worn while these medications are being used.

What are eyelid allergies (also called contact eye allergies)?

Contact eye allergies are essentially contact dermatitis of the eyelids. This is allergic inflammation of the eyelid from direct contact with certain allergens. Women in particular may experience this problem due to allergic reactions to preservatives in eye products and makeup (for example, eye creams, eye pencils, mascara, and nail polish -- from rubbing the eye with the fingers). Other irritants include common over-the-counter (OTC) ointments such as neomycin/bacitracin/polymyxin (Neosporin or Bacitracin) as well as contact lens solutions (especially if they contain thimerosal). Symptoms that are similar to those of a poison ivy rash appear 24 to 48 hours after exposure to the offending agent. The eyelids may develop blisters, itching, and redness. The conjunctiva may also become red and watery. If the eyelids continually come into contact with the offending allergens, the lids may become chronically (long-term) inflamed and thickened.

The best treatment for eyelid allergies is avoidance of the sensitizing agent(s). Changing to hypoallergenic lens solutions, cosmetics, or topical eye products is usually necessary. Application of a mild topical corticosteroid cream for short periods will probably help. As is the case with atopic dermatitis, it is important to treat any secondary bacterial infection that may develop.

What conditions can be confused with eye allergies?

The following is a list of conditions, the symptoms of which are commonly confused with eye allergy.

  • Dry eye: This condition results from reduced tear production and is frequently confused with allergy. The main symptoms are usually burning, grittiness, or the sensation of "something in the eye." Dry eye usually occurs in people over 65 years of age and can certainly be worsened by oral antihistamines like diphenhydramine (Benadryl), hydroxyzine (Atarax), Claritin, or Zyrtec, sedatives, and beta-blocker medications.
  • Tear-duct obstruction: This is caused by a blockage in the tear passage that extends from the eyes to the nasal cavity. This condition is also typically seen in the elderly. The main complaint is watery eyes that do not itch. Allergy testing will be negative in this case.
  • Conjunctivitis due to infection can be caused by either bacteria or viruses. In bacterial infections, the eyes are often "bright red" and the eyelids stick together, especially in the morning. A discolored mucous discharge is often seen, so-called "dirty eyes." Viral conjunctivitis causes slight redness of the eyes and a glassy appearance from tearing. Adenovirus is a major cause of viral conjunctivitis. The herpes virus, such as that which causes chickenpox or shingles, can also affect the eye. Adenovirus infection is very contagious and may be spread by either direct contact, such as hand contact, or in contaminated swimming pools. You should seek medical attention if you suspect any of the above.
 

 

Allergy assist
  • If your eye itches and is "milky" red, it is most likely allergy.
  • If it burns, it is probably dry eye.
  • If it "sticks" in the morning and is bright red, it is usually bacterial or viral conjunctivitis.

How do we care for allergic eyes?

Most people with eye allergies treat themselves and do so quite effectively with OTC products. If these remedies are not working or if there is eye pain, extreme redness, or heavy discharge, you should seek medical advice. Some conditions, for example, are serious with potential sight-threatening complications if required treatment is delayed.

Allergy assist

Moistening the eyes with artificial tears helps to dilute accumulated allergens and also prevents the allergens from sticking to the conjunctiva. Tear substitutes may also improve the defense function of the natural tear film.

Avoid the triggers

Avoidance is once again the cornerstone of allergy treatment. It is particularly important to avoid both airborne and contact allergens. Remember, rubbing your eyes is a physical trigger and therefore must be avoided.

Topical antihistamines & decongestants

Antihistamine eyedrops work by blocking histamine receptors in the conjunctiva. The histamine, therefore, is unable to attach to the conjunctiva and exert its effects. They are effective in relieving itching but have little impact on swelling or redness. They have two advantages over antihistamine tablets; there is a quicker onset of action and less drying of the eye. The new generation of topical antihistamines includes emedastine difumarate (Emadine) and levocabastine (Livostin). The side effects of these medications include mild stinging and burning of the eyes upon use, headaches, and sleepiness. But treatment with antihistamines at the point of irritation is still preferable than treating systemically with oral antihistamines if possible.

Decongestants take the redness away as advertised. However, they do not help relieve itching. They act by shrinking the blood vessels on the conjunctiva. (They are not really effective against allergic eyes.) The decongestants, oxymetazdine (Visine LR) and tetrahydrozoline hydrochloride (Visine Original) are available OTC. They do have a potential for abuse and should not be used by people with narrow-angle glaucoma, an eye disease characterized by elevated pressure within the eye.

Allergy assist

The prolonged use of decongestant nasal sprays can produce a rebound phenomenon in which the medication begins to cause more congestion than it relieves. This phenomenon rarely occurs in the eyes with the repeated use of decongestant drops. The mucous membranes of the eye are different from those of the nose. The eyes can become irritated and less responsive to the drops, but unlike the nose, the eyes tend not to develop "rebound" redness.

Combination antihistamine-decongestant preparations can provide quick relief that lasts a few hours. They lessen the itch, redness, and swelling and are very useful for milder symptoms. Common combinations include pheniramine with naphcyoline hydrochloride (Naphcon-A or Opcon-A) and antazoline with naphazoline (Vasocon-A). Side effects are minimal, but the drops may become less effective if used for prolonged periods. They do have a potential for abuse and should not be used by people with narrow-angle glaucoma.

Topical mast-cell stabilizers

Mast-cell stabilizers prevent the release of chemical mediators of inflammation from the mast cells. These are effective for all eye allergies. The first of this class of drug was cromolyn sodium (Crolom or Opticrom), which is available OTC. This topical medicine has been effective for treating mild cases of vernal keratoconjunctivitis and probably mild allergic rhinoconjunctivitis and has no significant side effects. It does have a slow onset of action. The newer agent, lodoxamide (Alomide), is 2,500 times more potent than Crolom and has a faster onset of action. This prescription medicine may be used in children older than 2 years of age and has minimal side effects. One disadvantage is the need to use the drops four times a day, and long-term use is necessary to prevent symptoms.

The most effective mast-cell stabilizer, which also has antihistamine properties, is Patanol. Available by prescription, it is 250 times more effective than Alomide in relieving itching and redness. This drug provides rapid relief of itching and burning eyes. It can also prevent symptoms when used before an exposure or before the pollen season. The drops are very comfortable in the eye and can by used in children as young as 3 years old. The longer duration of action allows dosing of twice a day.

Another new product, ketotifen (Zaditor), also has dual mast-cell-stabilizing and antihistamine effects. It dramatically reduces itching and redness and gives more rapid relief within minutes.

 

Topical antiinflammatory drugs

Nonsteroidal antiinflammatory drugs (NSAIDS) are particularly useful in treating itchy eyes. They reduce redness and swelling to a lesser degree. Ketorolac (Acular) is a topical NSAID, which may cause temporary stinging and burning in 40% of users.

 

Steroid antiinflammatory eyedrops are very effective in treating eye allergies, but they are reserved for severe symptoms that are unresponsive to other treatments. They must be used with caution in people with bleeding tendencies because they can increase the bleeding risk. Since there are significant risks with long-term treatment, their use should be supervised by an ophthalmologist.

Caution must be taken, however, because of the potential side effects of the long-term use of steroids, even in eye drop form. Side effects of steroids include elevated pressure in the eyes and cataracts. The elevated pressure in the eyes can become glaucoma and lead to damage of the optic (eye) nerve and loss of vision. Cataracts are a clouding or opacification of the clear natural lens within the eye, which can interfere with vision. The purpose of the lens is to focus the light or images that enter the eye. Remember, however, that the side effects of steroids usually occur with long-term use and that steroid eyedrops may be very effective when used over the short term. Loteprednol etabonate (Alrex) is a new short-acting steroid with fewer side effects that shows great promise in the treatment of allergic eye disease.

 

Allergy alert

Topical steroids may cause or worsen glaucoma and result in cataracts with long-term use. About 500 drops of a high-dose preparation can cause cataracts. Also, remember that with topical steroid eyedrops, short-term, low-potency preparations are recommended and should only be used under the supervision of an ophthalmologist.

Systemic medications

Oral antihistamines, either OTC or prescription (non- or lightly sedating), may be used for itchy eyes. The OTC products may cause drowsiness, and both can cause drying of the eyes.

 

Allergy assist

In general, treating topical conditions with topical medications is preferable. Why involve the whole body when locally effective alternatives are available?

Allergy shots (immunotherapy)

When avoidance of offending allergens and local treatments are not effective, allergy shots may be indicated. Your allergist may suggest this form of treatment when other measures have been unsuccessful.

Here are a few general tips worth remembering:

  • Eyes that are dry may aggravate eye allergy symptoms. Tear substitutes, such as artificial tears, are an often forgotten but are an effective lubricant and a wonderful treatment.
  • Cold compresses may help, particularly with sudden allergic reactions and swollen eyes.
  • Keep eyedrops refrigerated since this makes application more soothing.

 

Eye Allergy At A Glance
  • Most allergic eye conditions are more irritating than dangerous.
  • Allergic or vernal keratoconjunctivitis may result in scarring of the cornea and visual problems.
  • Itchy eyes are probably allergic eyes.
  • Topical antihistamine/decongestant preparations are effective and safe for mildly itchy, red eyes.
  • Patanol, a topical mast-cell stabilizer, is a safe, highly effective, long-acting treatment.
  • Topical steroids should be used with caution and under the supervision of an ophthalmologist.
  • If in doubt, seek medical advice sooner rather than later.


Churg-Strauss Syndrome

 

View Asthma Slideshow Pictures

 

Asthma Slideshow Pictures View Asthma Slideshow Pictures
Take the Asthma Quiz! Take the Asthma Quiz!
10 Worst Cities for Asthma Slideshow Pictures View 10 Worst Cities for Asthma Slideshow Pictures

 

Medical Author: William C. Shiel Jr., MD, FACP, FACR
Medical Editor: Melissa Conrad Stöppler, MD

  • What is Churg-Strauss syndrome?
  • What causes Churg-Strauss syndrome?
  • What are symptoms of Churg-Strauss syndrome?
  • How is Churg-Strauss syndrome diagnosed?
  • How is Churg-Strauss syndrome treated?
  • What is the outlook (prognosis) for patients with Churg-Strauss syndrome?
  • Churg-Strauss Syndrome At A Glance
  • Find a local Pulmonologist in your town

What is Churg-Strauss syndrome?

Churg-Strauss syndrome is one of many forms of vasculitis. Vasculitis diseases are characterized by inflammation of blood vessels. Churg-Strauss syndrome, in particular, occurs in patients with a history of asthma or allergy and features inflammation of blood vessels (also referred to as angiitis) in the lungs, skin, nerves, and abdomen. The blood vessels involved in Churg-Strauss syndrome are small arteries and veins.

What causes Churg-Strauss syndrome?

Churg-Strauss syndrome is rare. The cause of the syndrome is not known, but it involves an abnormal over-activation of the immune system in a person with underlying bronchospastic lung disease (asthma). While Churg-Strauss syndrome has been reported to be associated with certain asthma medications, called leukotriene modifiers, whether they actually cause the disease or whether the patients that take them have more severe asthma that lends a tendency toward the development of Churg-Strauss is not yet clear.

What are symptoms of Churg-Strauss syndrome?

Churg-Strauss syndrome causes fever, weight loss, and sinus or nasal passage inflammation in the patient with asthma. Fatigue is common. Sometimes the asthma actually improves somewhat as the disease intensifies elsewhere. Cough, shortness of breath, and chest pain can occur as the lungs are affected by vasculitis.

Skin lumps, called nodules, can appear on the extremities. Diarrhea and pain in the belly occur due to blood vessel inflammation within the abdomen. The bladder and prostate gland can become inflamed.

Numbness or weakness of the extremities is the result of nerve injury from the vasculitis. If the brain is affected, seizures or confusion can occur.

How is Churg-Strauss syndrome diagnosed?

Churg-Strauss syndrome is suggested when the symptoms described above occur in a patient with a history of asthma.

Abnormalities of the lungs, skin, and nerves might be noted by the doctor during the examination. Blood pressure can be elevated.

Blood examination generally shows elevated levels of an uncommon white blood cell, called an eosinophil, and other white blood cells are also elevated in number. Kidney function blood tests and urinalysis can be abnormal when the kidneys are affected (which is not common).

If the lungs are inflamed, the chest x-ray image or CT scan of the chest can demonstrate areas of inflammation.

The ultimate test for the diagnosis is a biopsy of involved tissue, which demonstrates a characteristic pattern of inflammation visible under a microscope. Eosinophil are also seen accumulated in the abnormal tissue.

How is Churg-Strauss syndrome treated?

The treatment of patients with Churg-Strauss syndrome is directed toward both immediately quieting the inflammation of the blood vessels (vasculitis) and suppressing the immune system. Treatment usually includes high doses of cortisone-related medication (such as prednisone or prednisolone) to calm the inflammation and suppression of the active immune system with cyclophosphamide (Cytoxan).

 

Traditionally, cyclophosphamide has been given for a year or more in patients with Churg-Strauss syndrome. In a research study, Churg-Strauss syndrome patients did equally well if treated with cyclophosphamide for 6 or for 12 months. This study suggests that doctors might now be able to recommend a shorter (and, therefore, less toxic) course of Cytoxan for patients with Churg-Strauss syndrome.

What is the outlook (prognosis) for patients with Churg-Strauss syndrome?

Churg-Strauss syndrome is a serious disease that can be fatal. Untreated it is extremely dangerous and threatens the organs that are affected. With aggressive treatment and monitoring it can be quieted and total inactivation of the disease (remission) is possible.

Churg-Strauss Syndrome AT A Glance
  • Churg-Strauss syndrome is a disease characterized by inflammation of the blood vessels.
  • Churg-Strauss syndrome occurs in patients with a history of asthma or allergy.
  • Symptoms of Churg-Strauss syndrome include fatigue, weight loss, nasal passage inflammation, numbness, and weakness.
  • The ultimate test for the diagnosis is a biopsy of involved tissue.
  • Treatment of Churg-Strauss syndrome involves stopping inflammation and suppressing the immune system.


Henoch-Schonlein Purpura (HSP)
or
Anaphylactoid Purpura

 

View the RA Slideshow Pictures
Rheumatoid Arthritis Slideshow Pictures Rheumatoid Arthritis
Joint-Friendly Exercises Slideshow Pictures Joint-Friendly Exercises
Simple Exercises to Relieve OA Pain Slideshow Simple Exercises to Relieve Osteoarthritis Pain Slideshow

Medical Author: William C. Shiel Jr., MD, FACP, FACR
Medical Editors: Dennis Lee, MD, and Melissa Conrad Stöppler, MD

  • What is Henoch-Schonlein purpura (HSP)?
  • What causes HSP?
  • What are symptoms of HSP?
  • How is HSP diagnosed?
  • What is the treatment for HSP?
  • What is the prognosis for patients with HSP?
  • Henoch-Schonlein Purpura At A Glance
  • Patient Discussions: Henoch-Schonlein Purpura - Symptoms
  • Patient Discussions: Henoch-Schonlein Purpura - Describe Your Experience

What is Henoch-Schonlein purpura (HSP)?

Henoch-Schonlein purpura (HSP) is a form of blood vessel inflammation or vasculitis. There are many different conditions that feature vasculitis. Each of the forms of vasculitis tends to involve certain characteristic blood vessels. HSP affects the small vessels called capillaries in the skin and frequently the kidneys. HSP results in skin rash (most prominent over the buttocks and behind the lower extremities) associated with joint inflammation (arthritis) and sometimes cramping pain in the abdomen. Henoch-Schonlein purpura is also referred to as anaphylactoid purpura.

What causes HSP?

HSP occurs most often in the spring and frequently follows an infection of the throat or breathing passages. HSP seems to represent an unusual reaction of the body's immune system that is in response to this infection (either bacteria or virus). Aside from infection, drugs can also trigger the condition. HSP occurs most commonly in children, but people of all age groups can be affected.

What are symptoms of HSP?

Classically, HSP causes skin rash, pain in the abdomen, and joint inflammation (arthritis). Not all features need be present for the diagnosis. The rash of skin lesions appears in gravity-dependent areas, such as the legs. The joints most frequently affected with pain and swelling are the ankles and the knees. Patients with HSP can develop fever. Inflammation of the blood vessels in the kidneys can cause blood and/or protein in the urine. Seriouhttp://ruaipharmaceuticals.com/administrator/index.php?option=com_content&sectionid=-1&task=edit&cid[]=57s kidney complications are infrequent but can occur.

Symptoms usually last approximately a month. Recurrences are not frequent but do occur.

How is HSP diagnosed?

HSP is usually diagnosed based on the typical skin, joint, and kidney findings. Throat culture, urinalysis, and blood tests for inflammation and kidney function are used to suggest the diagnosis. A biopsy of the skin, and less commonly kidneys, can be used to demonstrate vasculitis. Special staining techniques (direct immunofluorescence) of the biopsy specimen can be used to document antibody deposits of IgA in the blood vessels of involved tissue.

What is the treatment for HSP?

While HSP is generally a mild illness that resolves spontaneously, it can cause serious problems in the kidneys and bowels. The rash can be very prominent, especially on the lower extremities.

The treatment of HSP is directed toward the most significant area of involvement. Joint pain can be relieved by antiinflammatory medications such as aspirin or ibuprofen (Motrin). Some patients can require cortisone medications, such as prednisone or prednisolone, especially those with significant abdominal pain or kidney disease. With more severe kidney disease, involvement called glomerulonephritis or nephritis, cyclophosphamide (Cytoxan), azathioprine (Imuran), or mycophenolate mofetil (Cellcept) have been used to suppress the immune system. Infection, if present, can require antibiotics.

 

What is the prognosis for patients with HSP?

The prognosis for patients with HSP is generally excellent. Nearly all patients have no long-term problems. The kidney is the most serious organ involved when it is affected. Rarely, patients can have serious long-term kidney damage or an abnormal bowel folding called intussusception. Some patients have recurrences of symptoms, particularly skin rash, for months to a year after the onset of the illness.

Recent data show that HSP in adults is generally more severe than in children. Adults have more severe kidney involvement and can require more aggressive treatment. The ultimate outcome, however, is usually very good for both adults and children.

Henoch-Schonlein Purpura At A Glance
  • Henoch-Schonlein purpura is a particular form of blood vessel inflammation called vasculitis.
  • Henoch-Schonlein purpura frequently follows an infection of the throat or breathing passages, but it can be induced by certain medications.
  • Henoch-Schonlein purpura causes skin rash, pain in the abdomen, and joint inflammation (arthritis).
  • The treatment of Henoch-Schonlein purpura is directed toward the most significant area of involvement.
  • The prognosis for patients with Henoch-Schonlein purpura is generally excellent.


Anaphylaxis
(Severe Allergic Reaction)

 

View Slideshow Pictures

 

10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
Nasal Allergy Relief Slideshow Pictures Nasal Allergy Relief Slideshow Pictures

Revising Medical Author: Jerry R. Balentine, DO, FACEP
Revising Medical Editor: Melissa Conrad Stöppler, MD

  • Introduction to anaphylaxis
  • What does anaphylaxis mean?
  • How common is anaphylaxis?
  • What are common causes of anaphylaxis?
  • What are the signs of anaphylaxis?
  • What are anaphylaxis symptoms?
  • What happens after the symptoms begin?
  • Are there any disorders that appear similar to anaphylaxis?
  • How is anaphylaxis diagnosed?
  • How do we manage anaphylaxis?
  • What are emergency measures for anaphylaxis?
  • Can anaphylaxis be prevented?
  • Anaphylaxis At A Glance
  • Patient Discussions: Anaphylaxis - Symptoms and Signs
  • Patient Discussions: Anaphylaxis - Describe Your Experience
  • Find a local Doctor in your town

Introduction to anaphylaxis

Anaphylaxis refers to a rapidly developing and serious allergic reaction that affects a number of different areas of the body at one time. Severe anaphylactic reactions can be fatal. Most people experience allergy symptoms only as a minor annoyance. However, a small number of people are susceptible to a reaction that can lead to shock or even death.

Anaphylaxis is often triggered by substances that are injected or ingested and thereby gain access into the blood stream. An explosive reaction involving the skin, lungs, nose, throat, and gastrointestinal tract can then result. Although severe cases of anaphylaxis can occur within seconds or minutes of exposure and be fatal if untreated, many reactions are milder and can be ended with prompt medical therapy.

What does anaphylaxis mean?

To fully understand this term, we need to go back almost 100 years. The story begins on a cruise aboard Prince Albert I of Monaco's yacht. The Prince had invited two Parisian scientists to perform studies on the toxin produced by the tentacles of a local jellyfish, the Portuguese Man of War. Charles Richet and Paul Portier were able to isolate the toxin and tried to vaccinate dogs in the hope of obtaining protection, or "prophylaxis," against the toxin. They were horrified to find that subsequent very small doses of the toxin unexpectedly resulted in a new dramatic illness that involved the rapid onset of breathing difficulty and resulted in death within 30 minutes. Richet and Portier termed this "anaphylaxis" or "against protection." They rightly concluded that the immune system first becomes sensitized to the allergen over several weeks and upon re-exposure to the same allergen may result in a severe reaction. An allergen is a substance that is foreign to the body and can cause an allergic reaction in certain people.

Allergy Facts
  • The first documented case of presumed anaphylaxis occurred in 2641 B.C. when Menes, an Egyptian pharaoh, died mysteriously following a wasp or hornet sting. Later, in Babylonian times, there are two distinct references to deaths due to wasp stings.
  • Charles Richet was awarded the Nobel Prize in 1913 for his work on anaphylaxis.

Richet went on to suggest that the allergen must result in the production of a substance, which then sensitized the dogs to react in such a way upon re-exposure. This substance turned out to be IgE.

In the first part of the 20th century, anaphylactic reactions were most commonly caused by tetanus diphtheria vaccinations made from horse serum. Today, human serum is used for tetanus prevention, and the most common causes of anaphylaxis are now penicillin and other antibiotics, insect stings, and certain foods.

Allergy Fact

In 1956, Mary Hewitt Loveless showed that the injection of wasp venoms could cause anaphylaxis in individuals allergic to wasps. She subsequently used wasp extracts to successfully immunize such individuals.

How common is anaphylaxis?

The exact prevalence of anaphylaxis is unknown. The available statistics probably underestimate the true frequency because reactions are not always reported. Milder reactions may be attributed to an asthma attack or a sudden episode of hives. More serious, fatal episodes might be reported as a heart attack since the indicative signs of hives, swollen throat, and asthma can fade quickly. Thus, it is quite possible that even the true incidence of fatalities due to anaphylaxis is both under- recognized and under-reported. The importance of awareness, early recognition, and prompt treatment of this disorder must be stressed.

 

What are common causes of anaphylaxis?

The causes of anaphylaxis are divided into two major groups:

  • IgE mediated: This form is the true anaphylaxis that requires an initial sensitizing exposure, the coating of mast cells and basophils (cells in the blood and tissue that secrete the substances that cause allergic reactions, known as mediators) by IgE, and the explosive release of chemical mediators upon re-exposure.
  • Non-IgE mediated: These reactions, the so called "anaphylactoid" reactions, are similar to those of true anaphylaxis, but do not require an IgE immune reaction. They are usually caused by the direct stimulation of the mast cells and basophils. The same mediators as occur with true anaphylaxis are released and the same effects are produced. This reaction can happen, and often does, on initial as well as subsequent exposures, since no sensitization is required.

 

The terms anaphylaxis and anaphylactoid (meaning "like anaphylaxis") are both used to describe this severe, allergic reaction. Anaphylaxis is used to describe reactions that are initiated by IgE and anaphylactoid is used in reference to reactions that are not caused by IgE. The effects of the reactions are the same, however, and are generally treated in the same manner. Often, they can not be distinguished initially.

Although it may appear that IgE mediated anaphylaxis occurs upon a first exposure to a food, drug, or insect sting, there must have been a prior, and probably unwitting, sensitization from a previous exposure. You may not remember an uneventful sting or be aware of "hidden" allergens in foods.

What are the signs of anaphylaxis?

It is worth mentioning a few general observations regarding the features of anaphylactic reactions. Be aware, however, that these guidelines are not always consistent or reliable for a particular individual.

  • The severity of the reaction varies from person to person.
  • Subsequent reactions to the same trigger are typically similar in nature.
  • The more rapid the onset of symptoms, the more severe the reaction is likely to be.
  • A history of allergic disease (rhinitis, eczema, asthma) does not increase the risk of developing IgE mediated anaphylaxis, but it does incline the person to a non-IgE mediated reaction.
  • Underlying asthma may result in a more severe reaction and can be more difficult to treat.
  • The risk of anaphylaxis may diminish over time if there are no repeated exposures or reactions. However, a person at risk should always expect the worst and be prepared.

 

What are anaphylaxis symptoms?

The symptoms of an anaphylactic reaction may occur within seconds of exposure, or be delayed 15 to 30 minutes, or even an hour or more after exposure (typical of reactions to aspirin and similar drugs). Early symptoms are often related to the skin and include:

 
  • Flushing (warmth and redness of the skin),
  • itching (often in the groin or armpits), and
  • hives.

These symptoms are often accompanied by:

  • a feeling of "impending doom,"
  • anxiety, and
  • sometimes a rapid, irregular pulse.

Frequently following the above symptoms, throat and tongue swelling results in hoarseness, difficulty swallowing, and difficulty breathing.

Symptoms of rhinitis (hay fever) or asthma may occur causing:

  • a runny nose,
  • sneezing, and wheezing, which may worsen the breathing difficulty,
  • vomiting, diarrhea, and stomach cramps may develop.

About 25% of the time, the mediators flooding the blood stream cause a generalized opening of capillaries (tiny blood vessels) which results in a drop in blood pressure, lightheadedness, or even loss of consciousness. These are the typical features of anaphylactic shock.

What happens after the symptoms begin?

There are three possible outcomes:

  1. The signs and symptoms may be mild and fade spontaneously or be quickly ended by administering emergency medication. In this outcome, the symptoms do not subsequently recur from this particular exposure.

  2. After initial improvement, the symptoms may recur within 4 to 12 hours (late phase reaction) and require additional treatment and close observation. Recent evidence suggests that a late phase reaction occurs in fewer than 10% of cases.

  3. Lastly, the reaction may be persistent and more severe, thus requiring intensive medical treatment and hospitalization. This may occur up to 20% of the time with certain exposures.

Epinephrine, which is also known as "adrenaline," is a drug that acts immediately to cause the blood vessels to contract, thereby preventing fluid leakage. It is one of the medications frequently used to treat anaphylaxis. Epinephrine also helps relax the bronchial tubes, thus relieving breathing difficulty. It also lessens stomach cramps and stops itching and hives. More importantly, epinephrine helps prevent the release of more mediators of the allergic reaction. In addition to epinephrine, other medications and IV fluids and oxygen will probably be administered as well. The choice of interventions will depend on the severity of the reaction the patient experiences.

 

Are there any disorders that appear similar to anaphylaxis?

Several disorders may appear similar to anaphylaxis. Fainting (vaso-vagal reaction) is the reaction that is most likely to be confused with anaphylaxis. The key differences are that in a fainting episode, the affected person has a slow pulse, cool and pale skin, and no hives or difficulty breathing. Other conditions, such as heart attacks, blood clots to the lungs, septic shock, and panic attacks can also be confused with anaphylaxis.

 


 

10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
Nasal Allergy Relief Slideshow Pictures Nasal Allergy Relief Slideshow Pictures

In this Article

  • Introduction to anaphylaxis
  • What does anaphylaxis mean?
  • How common is anaphylaxis?
  • What are common causes of anaphylaxis?
  • What are the signs of anaphylaxis?
  • What are anaphylaxis symptoms?
  • What happens after the symptoms begin?
  • Are there any disorders that appear similar to anaphylaxis?
  • How is anaphylaxis diagnosed?
  • How do we manage anaphylaxis?
  • What are emergency measures for anaphylaxis?
  • Can anaphylaxis be prevented?
  • Anaphylaxis At A Glance
  • Find a local Doctor in your town

How is anaphylaxis diagnosed?

Once you think that you might have had an anaphylactic reaction, the first order of business is to seek emergency care. Once the acute reaction has been treated you should follow-up with your doctor who will probably recommend seeing an allergist. The allergist will assess whether or not the reaction was indeed allergic in nature. Usually, a careful and detailed medical history and selected blood or skin tests can identify the cause. Be prepared to recall your activities before the event, the food and medications you ingested, and whether or not you had any contact with rubber products.

Table 1: The Common Causes of Anaphylaxis

Causes - IgE Mediated Examples
Medications Penicillin, Cephalosporin, Anesthetics, Streptokinase, Others
Insect Stings Hornet, Wasp, Yellow Jacket, Honey Bee, Fire Ant
Foods Peanuts, Treenuts, Fish, Shellfish, Eggs, Milk, Soy, Wheat
Vaccines Allergy Shots, Egg and Gelatin based vaccines
Hormones Insulin, Possibly Progesterone
Latex Rubber Products
Animal/Human Proteins Horse Serum (used in some snake anti-venoms)
Causes - Non IgE Mediated Examples
Medication Non-steroidal Anti-inflammatories (Aspirin, Motrin, etc.), Morphine, Muscle Relaxants (Robaxin, Norflex, and others), Gamma Globulin
X-ray Dye
Preservatives Sulfites
Physical Exercise, Heat-Induced Urticaria (Hives), Cold- Induced Urticaria
Idiopathic Unknown Cause

How do we manage anaphylaxis?

The optimal management of anaphylaxis saves lives. An affected or at-risk person must be aware of possible triggers and early warning signs. If you are prone to these reactions, you must be familiar with the use of emergency anaphylaxis treatment kits and always have them with you. Emergency measures and prevention are central to management. As always, allergic diseases are best treated by avoidance measures, which will be reviewed in detail below.

What are emergency measures for anaphylaxis?

If you suspect that you or someone you are with is having an anaphylactic reaction, the following are important first aid measures. In general, try to perform these in the order that they are presented.

  • Call emergency services or 911 IMMEDIATELY.
  • If the patient has an epi-pen, inject epinephrine immediately. The shot is given into the outer thigh and can be administered through light fabric. Rub the site to improve absorption of the drug.
  • Place a conscious person lying down and elevate the feet if possible.
  • Stay with the person until help arrives.
  • If trained, begin CPR if the person stops breathing or doesn't have a pulse.

 

Allergy Assist

Shots of epinephrine can be given through light clothing such as trousers, skirts, or stockings. Heavy garments may have to be removed prior to injecting. Only inject epinephrine if the patient has a history of anaphylactic reactions or under guidance of a healthcare provider.

After 10 to 15 minutes, if the symptoms are still significant, you can inject another dose of epinephrine if available. Even after the reaction subsides you need to go to an emergency department immediately. Other treatments may be given, such as oxygen, intravenous fluids, breathing medications, and possibly more epinephrine. Steroids and antihistamines may be given but these are often not helpful initially and do not take the place of epinephrine. However, they may be more useful in preventing a recurrent delayed reaction.

Do not be surprised if epinephrine makes you feel shaky and causes a rapid, pounding pulse. These are normal side effects and are not dangerous except for those with severe heart problems.

Two situations deserve special attention at this point since they are not covered elsewhere but are particularly interesting.

  1. In the 1970's, it was noted that exercise could cause anaphylaxis. Exercise-induced anaphylaxis (EIA) usually occurs with prolonged, strenuous exercise. Conditioned athletes such as marathon runners are frequently affected. The reaction may occur while exercising shortly after eating a meal, after eating specific foods (for example, lettuce, shellfish, or celery) or after taking aspirin. It appears as though food or aspirin loads the gun and exercise pulls the trigger. Early symptoms are usually flushing and itching, which may progress to other typical symptoms of anaphylaxis if the exercise continues. Pre-medication with antihistamines or other drugs does not consistently prevent EIA. Exercise avoidance is the most effective treatment. If this is not feasible, exercising with a "buddy" and carrying emergency kits is mandatory.

  1. When no cause can be found for anaphylaxis, it is termed idiopathic. Recent reports suggest that 25% of all episodes of anaphylaxis are idiopathic. Many of those affected have underlying allergy or asthma conditions. Extensive allergy testing for foods may uncover an unusual food allergy that is responsible for these reactions. For frequent episodes of anaphylaxis, your physician may recommend a combination of antihistamine, cortisone, and a medication to widen the airways of the lungs (bronchial dilator) to help reduce the severity of attacks.

Can anaphylaxis be prevented?

Preventing anaphylaxis is the ideal form of treatment. However, that may not always be easy since insect stings are frequently unanticipated and allergic foods are often hidden in a variety of different preparations. A consultation with an allergist is vital in helping you identify the trigger(s) and providing you with information and instruction on how to best avoid them. You will learn how to use emergency kits and how to become prepared for any reaction in the future.

These are three situations in which preventive treatment might be offered by the allergist.

  1. Allergy shots may be suggested to some people with wasp, yellow jacket, hornet, honey bee, or fire ant reactions. This form of treatment gives 98% protection against the first four insect reactions, though somewhat less protection against fire ant reactions.

  1. Pre-medication is most helpful in preventing anaphylaxis from x-ray dyes. Alternative dyes that are less likely to cause reactions may be available.

  1. Desensitization to problematic medications is often effective. This process is accomplished by gradually increasing the amount of the medication given under controlled conditions. Sensitivities to penicillin, sulfa drugs, and insulin have been successfully treated in this way.

Anyone known to be at risk for anaphylaxis should wear a Medic-Alert bracelet that clearly states the allergic trigger, the risk of anaphylaxis, and the availability of an epinephrine kit.

Allergy Assist

People with anaphylaxis to medications should take new medications by mouth whenever possible since the risk of anaphylaxis is higher with injections.

 

Table 2: Basic Avoidance Measures for Anaphylaxis

Trigger Avoidance Principle
Drugs/Medications
  • Advise all health care personnel of your allergies.
  • Ask your doctor whether the prescribed medication contains the drug(s) you are allergic to.
  • Take all drugs by mouth if possible.
Insect Stings
  • Avoid areas such as outdoor garbage, barbecues, and insect nests.
  • Avoid bright clothing, perfume, hair spray or lotion that might attract insects.
  • Wear long sleeved clothing, long trousers, and shoes while outdoors
Food
  • Carefully read all labels.
  • Ask what the ingredients are when eating out.
  • Avoid foods that may cross react such as bananas, kiwi fruit, and avocado.
Latex
  • Avoid all Latex products.
  • Ask if your hospital has Latex safety issues if you need to be hospitalized.

Since avoidance is not fail safe, a person at risk for an anaphylactic reaction must be adequately prepared in an emergency to handle a reaction. It is recommended that everyone at risk carry epinephrine injection kits designed for self-administration. These kits are available by prescription only and come in two forms:

  • Epi-pen is a spring-loaded automatic syringe that delivers a predetermined dose (0.3mg) when the tip is pressed hard for several seconds. An Epi-pen junior is available for children under 33 pounds and contains half of the dose.
  • Ana-kit contains a preloaded syringe and needles with two 0.3mg doses of epinephrine. These are injected under the skin or into the muscle of the thigh. An antihistamine, alcohol swab, and a tourniquet are included in the kit.

Here are some important points to remember regarding the kits:

  • Ask you doctor to explain the use of the kit carefully and practice with the demonstrator kit.
  • Check expiration dates and replace outdated kits.
  • Keep kits out of direct sunlight, which may affect the drug.
  • Additional kits should be brought to school or work.
  • Always have kits with you or readily available.
  • Make sure that your friends, relatives, exercise buddies, and co-workers are aware of your condition and know what to do in case of a reaction.
Anaphylaxis At A Glance
  • Anaphylaxis is the most severe allergic reaction and is potentially life threatening.
  • Anaphylaxis is rare. The vast majority of people will never have an anaphylactic reaction.
  • The most common causes of anaphylaxis include drugs, such as penicillin, insect stings, foods, x-ray dye, latex, and exercise.
  • The symptoms of anaphylaxis may vary from hives, tongue swelling, and vomiting, to shock.
  • If you are at risk, avoidance is the best form of treatment.
  • If you have a history of serious allergic reaction, always have an epinephrine kit available - it could save your life.


Hay Fever
(Allergic Rhinitis)

 

View Slideshow Pictures

 

10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
Nasal Allergy Relief Slideshow Pictures Nasal Allergy Relief Slideshow Pictures

 

Medical Author: Melissa Conrad Stöppler, MD
Medical Editor: William C. Shiel Jr., MD, FACP, FACR

  • What is hay fever? What are the symptoms and signs?
  • Why does an allergic reaction occur?
  • What causes allergic rhinitis?
  • When and where does allergic rhinitis occur?
  • How is allergic rhinitis diagnosed, and how are allergies identified?
  • How are allergies treated?
  • Hay Fever At A Glance
  • Find a local Asthma & Allergy Specialist in your town

Hay fever affects up to 30% of all Americans, including up to 40% of children and 10%-30% of adults. Over $1 billion is spent each year in this country to treat this disorder, and millions of school and work days each year are lost by sufferers of hay fever symptoms. These figures are probably an underestimate because many of those affected may attribute their discomfort to a chronic cold. Although childhood hay fever tends to be more common, this condition can occur at any age and usually occurs after years of repeated inhalation of allergic substances. The incidence of allergic disease has dramatically increased in the U.S. and other developed countries over recent decades.

What is hay fever? What are the symptoms and signs?

Hay fever is a misnomer. Hay is not a usual cause of this problem, and it does not cause fever. Early descriptions of sneezing, nasal congestion, and eye irritation while harvesting field hay promoted this popular term. Allergic rhinitis is the correct term used to describe this allergic reaction, and many different substances cause the allergic symptoms noted in hay fever. Rhinitis means "irritation of the nose" and is a derivative of rhino, meaning nose. Allergic rhinitis which occurs during a specific season is called "seasonal allergic rhinitis." When it occurs throughout the year, it is called "perennial allergic rhinitis." Rhinosinusitis is the medical term that refers to inflammation of the nasal lining as well as the lining tissues of the sinuses. This term is sometime used because the two conditions frequently occur together.

Symptoms of allergic rhinitis, or hay fever, frequently include nasal congestion, a clear runny nose, sneezing, nose and eye itching, and excess tear production in the eyes. Postnasal dripping of clear mucus frequently causes a cough. Loss of the sense of smell is common, and loss of taste sense occurs occasionally. Nose bleeding may occur if the condition is severe. Eye itching, redness, and excess tears in the eyes frequently accompany the nasal symptoms. The eye symptoms are referred to as "allergic conjunctivitis" (inflammation of the whites of the eyes). These allergic symptoms often interfere with one's quality of life and overall health.

Allergic rhinitis can lead to other diseases such as sinusitis and asthma. Many people with allergies have difficulty with social and physical activities. For example, concentration is often difficult while experiencing allergic rhinitis.

Why does an allergic reaction occur?

An allergic reaction occurs when the immune system attacks a usually harmless substance called an allergen that gains access to the body. To more simply describe this complex immune process, we will make an analogy to a war within the body. The immune system calls upon a protective substance called immunoglobulin E (IgE) antibodies ("E" for "erythema" or redness) to fight these invading allergic substances or allergens. Even though everyone has some IgE, an allergic person has an unusually large army of these IgE defenders -- in fact, too many for his/her own good. This army of IgE antibodies attacks and engages the invading army of allergic substances of allergens.

As is often the case in war, innocent bystanders are affected in battle. These innocent bystanders are special cells called mast cells. These cells are frequently injured during the warring of the IgE antibodies and the allergic substances. When a mast cell is injured, it releases a variety of chemicals into the tissues and blood, one of which is known as histamine. These chemicals frequently cause allergic reactions. These chemicals are very irritating and cause itching, swelling, and fluid leaking from cells. Through various mechanisms, these allergic chemicals can cause muscle spasm and can lead to lung and throat tightening as is found in asthma and loss of voice.

What causes allergic rhinitis?

Any substance can cause an allergy if exposed to a person in the right way. But for all practical purposes and with few exceptions, allergic rhinitis is caused by proteins. Commonly, allergic rhinitis is a result of an allergic person coming in contact several times with protein from plants. Many trees, grasses, and weeds produce extremely small, light, dry protein particles called pollen. This pollen is spread by the wind and is inhaled. These pollen particles are usually the male sex cells of the plant and are smaller than the tip of a pin or less than 40 microns in diameter.

Even though pollen is usually invisible in the air, pollen is a potent stimulator of allergy. Pollen lodges in the nasal lining tissues (mucus membranes) and other parts of the respiratory tract where it initiates the allergic response. Up to 30% of Americans at times suffer from allergic rhinitis. A person is programmed to be allergic by his/her genetic makeup and is destined to be allergic from birth. Approximately one in four people with allergic rhinitis also has asthma.

How are allergies treated?

Avoidance of identified allergens is the most helpful factor in controlling allergy symptoms. Attempts to control the environment and avoidance measures often significantly aid in resolving symptoms. However, allergy avoidance is often not easy. A thorough discussion with your physician is needed, and control measures may be required daily.

If avoidance is not possible or does not relieve symptoms, additional treatment is needed. Many patients respond to medications that combat the effects of histamine, known as antihistamines. Antihistamines do not stop the formation of histamine, nor do they stop the conflict between the IgE and antigen. Therefore, antihistamines do not stop the allergic reaction but rather protect tissues from the effects of the allergic response.

The first-generation antihistamines, such as diphenhydramine (Benadryl), chlorpheniramine (Chlortrimaton), dimenhydrinate (Dramamine), brompheniramine (Dimetapp and others), clemastine fumarate (Tavist, Allerhist), and dexbrompheniramine (Drixoral) frequently cause mouth dryness and sleepiness as side effects. Newer, so-called "non-sedating" or second-generation antihistamines are also available. These include loratadine (Claritin), fexofenadine (Allegra), cetirizine (Zyrtec), fexofenidine (Allegra), and azelastine (Astelin Nasal Spray). In general, this group of antihistamines is slightly more expensive, has a slower onset of action, is longer acting, and induces less sleepiness. Discuss with your physician other antihistamine side effects that very occasionally occur (for example, urine retention in males, fast heart rate, and others). You should always discuss the potential side effects of any medication with your physician and/or pharmacist. A thorough review of specific antihistamines can be found under the Medications Center and more in the Nasal Allergy Medications article.

 

Decongestants help control allergy symptoms but not their causes. Decongestants shrink the swollen membranes in the nose and make it easier to breathe. Decongestants can be taken orally or by nasal spray. Decongestant nasal sprays should not be used for more than five days without a doctor's advice, and if so, usually only when accompanied by a nasal steroid. Decongestant nasal sprays often cause a so-called "rebound effect" if taken for too long. A rebound effect is the worsening of symptoms when a drug is discontinued. This is a result of a tissue dependence on the medication.

Some people with allergies need specialized prescription medications such as corticosteroids, cromolyn, and ipratropium (Atropine-like) nasal sprays. These nasal sprays do not cause the rebound effect noticed with decongestant nasal sprays. Cortisone nasal sprays are very effective in reducing the inflammation which causes swelling, sneezing, and a runny nose. Cortisone can also stop the allergy "war" by halting the formation of the many allergy chemicals described above. Many cortisone nasal sprays are on the market through prescription only. Fluticasone (Flonase) is one example, but many preparations are available.

 

Cromolyn is also an antiinflammatory medication. Although cromolyn is not as potent as cortisone, it has a very safe profile. Cromolyn must be used well in advance of anticipated allergy symptoms to be useful. Ipratropium nasal spray is available for drying a wet runny nose. It will not prevent allergic reactions. This is an atropine derivative and although usually very safe, a person sensitive to atropine should be cautious when taking this drug.

Montelukast (Singulair) is an inhibitor of leukotriene action, another chemical involved in the allergic reaction. This medication is used for therapy of asthma and has also been approved for treatment of allergic rhinitis. It has been shown to be most effective in those for whom significant congestion is a primary complaint. It may also be used in some cases together with second-generation antihistamines.

 

If antihistamines and nasal sprays are not effective or not tolerated by the patient, other modalities of therapy are available. Allergy desensitization or immunotherapy may be needed. Allergy immunotherapy stimulates the immune system with gradually increasing doses of the substances to which a person is allergic. Since the patient is being exposed to the allergy-inducing substance, an allergic reaction can occur, and this treatment should be supervised by an allergy specialist. Although the exact way allergy desensitization works is not completely known, allergy injections appear to modify or stop the allergy "war" by reducing the strength of the IgE and its effect on the mast cells. This form of treatment is very effective for allergies to pollen, mites, cats, and especially stinging insects (for example, bees). Allergy immunotherapy usually requires a series of injections and takes three months to one year to become effective. The required length of treatment may vary, but three years is a typical course. Frequent office visits are necessary.

The success rate of an allergy desensitization program in significantly reducing symptoms can be up to about 80%. The duration of the effect of allergy immunotherapy should last many years, if not a lifetime. Although rare (one in 2-5 million injections given), serious allergy reactions can occur while receiving allergy injections. One cannot predict who will have a severe reaction. Even after years of receiving allergy shots, a patient can experience a reaction.

Hay Fever At A Glance
  • Hay fever (Allergic rhinitis) is common.
  • Allergy symptoms mimic chronic colds.
  • Allergic rhinitis can lead to other diseases.
  • The best way to treat an allergy condition is to identify the allergic substance and avoid it.
  • Effective treatment is available in many forms.


Allergy/Allergies

 

View Slideshow Pictures

 

10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
Nasal Allergy Relief Slideshow Pictures Nasal Allergy Relief Slideshow Pictures

 

Medical Author: Alan Szeftel, MD, FCCP
Medical Editor: William C. Shiel Jr., MD, FACP, FACR

  • Allergy facts
  • What does an allergy mean?
  • What causes allergies?
  • Who is at risk and why?
  • What are common allergic conditions, and what are allergy symptoms and signs?
  • Hay Fever
  • Asthma
  • Allergic Eyes
  • Allergic Eczema
  • Hives
  • Allergic Shock
  • Where are allergens? Everywhere
  • In the air we breathe
  • In what we ingest
  • Touching our skin
  • Injected into our body
  • Patient Discussions: Allergy - Symptoms
  • Patient Discussions: Allergies - Describe Your Experience
  • Find a local Asthma & Allergy Specialist in your town

Allergy facts

  • Allergy involves an exaggerated response of the immune system.
  • The immune system is the body's organized defense mechanism against foreign invaders, particularly infections.
  • Allergens are substances that are foreign to the body and can cause an allergic reaction.
  • IgE is the allergy antibody.
  • Allergies can develop at any age.
  • Your risk of developing allergies is related to your parents' allergy history.

 

Introduction

In this review you will learn how allergy relates to the immune system. You will begin understanding how and why certain people become allergic. The most common allergic diseases are discussed briefly in this article.

What does an allergy mean?

An allergy refers to an exaggerated reaction by our immune system in response to bodily contact with certain foreign substances. It is exaggerated because these foreign substances are usually seen by the body as harmless and no response occurs in non- allergic people. Allergic people's bodies recognize the foreign substance and one part of the immune system is turned on. Allergy-producing substances are called "allergens." Examples of allergens include pollens, dust mite, molds, danders, and foods. To understand the language of allergy it is important to remember that allergens are substances that are foreign to the body and can cause an allergic reaction in certain people.

When an allergen comes in contact with the body, it causes the immune system to develop an allergic reaction in persons who are allergic to it. When you inappropriately react to allergens that are normally harmless to other people, you are having an allergic reaction and can be referred to as allergic or atopic. Therefore, people who are prone to allergies are said to be allergic or "atopic."

Austrian pediatrician Clemens Pirquet (1874-1929) first used the term allergy. He referred to both immunity that was beneficial and to the harmful hypersensitivity as "allergy." The word allergy is derived from the Greek words "allos," meaning different or changed and "ergos," meaning work or action. Allergy roughly refers to an "altered reaction." The word allergy was first used in 1905 to describe the adverse reactions of children who were given repeated shots of horse serum to fight infection. The following year, the term allergy was proposed to explain this unexpected "changed reactivity."

Allergy Fact
  • It is estimated that 50 million North Americans are affected by allergic conditions.
  • The cost of allergies in the United States is more than $10 billion dollars yearly.
  • Allergic rhinitis (nasal allergies) affects about 35 million Americans, 6 million of whom are children.
  • Asthma affects 15 million Americans, 5 million of whom are children.
  • The number of cases of asthma has doubled over the last 20 years.

What causes allergies?

To help answer this question, let's look at a common household example. A few months after the new cat arrives in the house, dad begins to have itchy eyes and episodes of sneezing. One of the three children develops coughing and wheezing, especially when the cat comes into her bedroom. The mom and the other two children experience no reaction whatsoever to the presence of the cat. How can we explain this?

The immune system is the body's organized defense mechanism against foreign invaders, particularly infections. Its job is to recognize and react to these foreign substances, which are called antigens. Antigens are substances that are capable of causing the production of antibodies. Antigens may or may not lead to an allergic reaction. Allergens are certain antigens that cause an allergic reaction and the production of IgE.

The aim of the immune system is to mobilize its forces at the site of invasion and destroy the enemy. One of the ways it does this is to create protective proteins called antibodies that are specifically targeted against particular foreign substances. These antibodies, or immunoglobulins (IgG, IgM, IgA, IgD), are protective and help destroy a foreign particle by attaching to its surface, thereby making it easier for other immune cells to destroy it. The allergic person however, develops a specific type of antibody called immunoglobulin E, or IgE, in response to certain normally harmless foreign substances, such as cat dander. To summarize, immunoglobulins are a group of protein molecules that act as antibodies. There are five different types; IgA, IgM, IgG, IgD, and IgE. IgE is the allergy antibody.

(In 1967, the husband and wife team of Kimishige and Teriko Ishizaka detected a previously unrecognized type of immunoglobulin in allergic people. They called it gamma E globulin or IgE.)

In the pet cat example, the dad and the youngest daughter developed IgE antibodies in large amounts that were targeted against the cat allergen, the cat dander. The dad and daughter are now sensitized or prone to develop allergic reactions on subsequent and repeated exposures to cat allergen. Typically, there is a period of "sensitization" ranging from months to years prior to an allergic reaction. Although it might occasionally appear that an allergic reaction has occurred on the first exposure to the allergen, there must have been a prior contact in order for the immune system to be poised to react in this way.

IgE is an antibody that all of us have in small amounts. Allergic persons, however, produce IgE in large quantities. Normally, this antibody is important in protecting us from parasites, but not from cat dander or other allergens. During the sensitization period, cat dander IgE is being overproduced and coats certain potentially explosive cells that contain chemicals. These cells are capable of causing an allergic reaction on subsequent exposures to the dander. This is because the reaction of the cat dander with the dander IgE irritates the cells and leads to the release of various chemicals, including histamine. These chemicals, in turn, cause inflammation and the typical allergic symptoms. This is how the immune system becomes exaggerated and primed to cause an allergic reaction when stimulated by an allergen.

On exposure to cat dander, the mom and the other two children produce other classes of antibodies, none of which cause allergic reactions. In these non-allergic members of the family, the dander particles are eliminated uneventfully by the immune system and the cat has no effect on them.

Figure 1

The Immune System
-
Foreign Substance

alt="-"
(cat dander, pollen, virus, bacteria)
**

Normal Immune Response

IgM, IgG, IgA, IgD and various immune cells respond to attack.


Exaggerated Immune Response

IgE is overproduced in response to cat dander, pollens, and other harmless allergens.

*

*

Foreign substance is eliminated.

Subsequent exposure results in an allergic reaction.

*

*

Non-Allergic Individual

Allergic Individual

Who is at risk and why?

Allergies can develop at any age, possibly even in the womb. They commonly occur in children but may give rise to symptoms for the first time in adulthood. Asthma may persist in adults while nasal allergies tend to decline in old age.

Why, you may ask, are some people "sensitive" to certain allergens while most are not? Why do allergic persons produce more IgE than those who are non-allergic? The major distinguishing factor appears to be heredity. For some time, it has been known that allergic conditions tend to cluster in families. Your own risk of developing allergies is related to your parents' allergy history. If neither parent is allergic, the chance that you will have allergies is about 15%. If one parent is allergic, your risk increases to 30% and if both are allergic, your risk is greater than 60%.

Although you may inherit the tendency to develop allergies, you may never actually have symptoms. You also do not necessarily inherit the same allergies or the same diseases as your parents. It is unclear what determines which substances will trigger a reaction in an allergic person. Additionally, which diseases might develop or how severe the symptoms might be is unknown.

Another major piece of the allergy puzzle is the environment. It is clear that you must have a genetic tendency and be exposed to an allergen in order to develop an allergy. Additionally, the more intense and repetitive the exposure to an allergen and the earlier in life it occurs, the more likely it is that an allergy will develop.

There are other important influences that may conspire to cause allergic conditions. Some of these include smoking, pollution, infection, and hormones.

What are common allergic conditions, and what are allergy symptoms and signs?

The parts of the body that are prone to react to allergies include the eyes, nose, lungs, skin, and stomach. Although the various allergic diseases may appear different, they all result from an exaggerated immune response to foreign substances in sensitive people. The following brief descriptions will serve as an overview of common allergic disorders.

Allergic Rhinitis

Allergic rhinitis ("hay fever") is the most common of the allergic diseases and refers to seasonal nasal symptoms that are due to pollens. Year round or perennial allergic rhinitis is usually due to indoor allergens, such as dust mites, animal dander, or molds. It can also be caused by pollens. Symptoms result from the inflammation of the tissues that line the inside of the nose (mucus lining or membranes) after allergens are inhaled. Adjacent areas, such as the ears, sinuses, and throat can also be involved. The most common symptoms include:

  • Runny nose
  • Stuffy nose
  • Sneezing
  • Nasal itching (rubbing)
  • Itchy ears and throat
  • Post nasal drip (throat clearing)

In 1819, an English physician, John Bostock, first described hay fever by detailing his own seasonal nasal symptoms, which he called "summer catarrh." The condition was called hay fever because it was thought to be caused by "new hay."

Asthma

Asthma is a breathing problem that results from the inflammation and spasm of the lung's air passages (bronchial tubes). The inflammation causes a narrowing of the air passages, which limits the flow of air into and out of the lungs. Asthma is most often, but not always, related to allergies. Common symptoms include:

  • Shortness of breath
  • Wheezing
  • Coughing
  • Chest tightness

Allergic Eyes

Allergic eyes (allergic conjunctivitis) is inflammation of the tissue layers (membranes) that cover the surface of the eyeball and the undersurface of the eyelid. The inflammation occurs as a result of an allergic reaction and may produce the following symptoms:

  • Redness under the lids and of the eye overall
  • Watery, itchy eyes
  • Swelling of the membranes

Allergic Eczema

Allergic eczema (atopic dermatitis) is an allergic rash that is usually not caused by skin contact with an allergen. This condition is commonly associated with allergic rhinitis or asthma and features the following symptoms:

  • Itching, redness, and or dryness of the skin
  • Rash on the face, especially children
  • Rash around the eyes, in the elbow creases, and behind the knees, especially in older children and adults (rash can be on the trunk of the body)

Hives

Hives (urticaria) are skin reactions that appear as itchy swellings and can occur on any part of the body. Hives can be caused by an allergic reaction, such as to a food or medication, but they also may occur in non-allergic people. Typical hive symptoms are:

  • Raised red welts
  • Intense itching

Allergic Shock

Allergic shock (anaphylaxis or anaphylactic shock) is a life-threatening allergic reaction that can affect a number of organs at the same time. This response typically occurs when the allergen is eaten (for example, foods) or injected (for example, a bee sting). Some or all of the following symptoms may occur:

  • Hives or reddish discoloration of the skin
  • Nasal congestion
  • Swelling of the throat
  • Stomach pain, nausea, vomiting
  • Shortness of breath, wheezing
  • Low blood pressure or shock

Shock refers to the insufficient circulation of blood to the body's tissues. Shock is most commonly caused by blood loss or an infection. Allergic shock is caused by dilated and "leaky" blood vessels, which result in a drop in blood pressure.

Where are allergens?

Everywhere...

We have seen that allergens are special types of antigens that cause allergic reactions. The symptoms and diseases that result depend largely on the route of entry and level of exposure to the allergens. The chemical structure of allergens affects the route of exposure. Airborne pollens, for example, will have little effect on the skin. They are easily inhaled and will thus cause more nasal and lung symptoms and limited skin symptoms. When allergens are swallowed or injected they may travel to other parts of the body and provoke symptoms that are remote from their point of entry. For example, allergens in foods may prompt the release of mediators in the skin and cause hives.

We will assume that allergens are defined as: the source of the allergy producing substance (for example, cat), the substance itself (cat dander), or the specific proteins that provoke the immune response (for example, Feld1). Feld1, from the Felis domesticus (the domesticated cat), is the most important chemical allergen in cat dander.

 

Allergens may be inhaled, ingested (eaten or swallowed), applied to the skin, or injected into the body either as a medication or inadvertently by an insect sting.

In the Air We Breathe

Breathing can be hazardous if you are allergic. Aside from oxygen, the air contains a wide variety of particles; some toxic, some infectious, and some "innocuous," including allergens. The usual diseases that result from airborne allergens are hay fever, asthma, and conjunctivitis. The following allergens are usually harmless, but can trigger allergic reactions when inhaled by sensitized individuals.

  • Pollens: trees, grasses, and/or weeds
  • Dust mites
  • Animal proteins: dander, skin, and/or urine
  • Mold spores
  • Insect parts: cockroaches

In What We Ingest

When foods or medications are ingested, allergens may gain access to the blood stream and become attached to specific IgE on cells in remote sites such as the skin or nasal membranes. The ability of allergens to travel explains how symptoms can occur in areas other than the gastrointestinal tract. Food allergy reactions may begin with tongue or throat swelling and may be followed by tingling, nausea, diarrhea, or stomach cramps. Nasal breathing difficulties or skin reactions may also be seen. The two main allergen groups that are ingested are:

  • Foods
  • Drugs (when taken by mouth): for example, antibiotics and aspirin
Allergy Assist The most common foods that cause allergic reactions are cow's milk, fish, shellfish, eggs, peanuts, tree nuts, soy, and wheat.

Touching Our Skin

Allergic contact dermatitis is an inflammation of the skin that is caused by a local allergic reaction. The majority of these localized skin reactions do not involve IgE, but are caused by cells of inflammation. The rash produced is similar to that of a poison ivy rash. It should be noted that when some allergens (for example, latex) come into contact with the skin, they are absorbed by the skin and can also potentially cause reactions throughout the body, not just the skin. For most people, however, the skin is a formidable barrier that can be only locally affected. Examples of allergic contact dermatitis include:

  • Latex (causes IgE and non-IgE reactions)
  • Plants (poison ivy and oak)
  • Dyes
  • Chemicals
  • Metals (nickel)
  • Cosmetics

Allergic contact dermatitis does not involve IgE antibody, but involves cells of the immune system which are programmed to react when triggered by a sensitizing allergen. Touching or rubbing a substance to which you were previously sensitized can trigger a skin rash.

Injected into Our Body

The most severe reactions can occur when allergens are injected into the body and gain direct access to the blood stream. This access carries the risk of a generalized reaction, such as anaphylaxis, which can be life-threatening. The following are commonly injected allergens that can cause severe allergic reactions:

  • Insect venom
  • Medications
  • Vaccines (including allergy shots)
  • Hormones (for example, insulin)


Nasal Allergy Medications

 

View Slideshow Pictures

 

10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
Nasal Allergy Relief Slideshow Pictures Nasal Allergy Relief Slideshow Pictures

 

  • Introduction
  • What's the difference between a controller and a reliever?
  • What are antihistamines?
  • How do antihistamines work?
  • What are first generation antihistamines (OTCs)?
  • What are second generation antihistamines (prescription)?
  • What are common side effects of antihistamines?
  • What are decongestants?
  • How do decongestants work?
  • When should I use topical decongestants?
  • What are side effects of decongestants?
  • What about combination antihistamine/decongestant preparations?
  • Nasal Steroid Sprays
  • Other nasal sprays that might help
  • Tips for proper use of nasal sprays
  • Nasal Allergy Medications At A Glance
  • Related nasal allergy medication article:
    Flonase - on RxList
  • Find a local Asthma & Allergy Specialist in your town

 

Introduction

Although they are the cornerstone of allergy treatment, avoidance measures are not always enough to manage all of the symptoms. When the symptoms of nasal allergies are mild or intermittent, antihistamines with or without decongestants can help. Very often, some relief can be found in taking over-the-counter (OTC) drugs and this is usually the first step an allergy sufferer will take. Self-medication, though, is frequently inadequate since OTC drugs cannot adequately treat the inflammation that develops in the nose. At this stage, anti-inflammatory medications are required, usually in the form of intra- nasal steroid sprays (sprayed into the nose).

The combination of an antihistamine (with or without a decongestant) and a topical nasal steroid spray will usually afford good relief with minimal side effects. The addition of ipratropium bromide nasal spray (Atrovent - an anticholinergic medication) is also very effective for a runny nose that has been unresponsive to prior treatments. Let's look at these medications in more detail to understand their role in the treatment of nasal allergy.

What's the difference between a controller and a reliever?

Throughout this section on allergy management, we will be referring to the various treatments as "controllers" or "relievers" of symptoms. Controllers are used to prevent symptoms by interfering with the underlying causes of the inflammatory response or the actions of chemical mediators. Examples of controllers include:

  • Drugs that block the attachment of histamine to special receptors on cells (e.g., antihistamines);
  • Drugs that prevent mast cells from releasing chemicals (e.g., Cromolyn); and,
  • Drugs that prevent or reduce inflammation that arises from an allergic reaction (e.g., steroids).

Other medications, called relievers, are used to alleviate symptoms without affecting the inflammation. They are also called "rescue" medications and in general provide only temporary relief. Relievers should only be used alone for mild or intermittent symptoms. Examples include:

  • Drugs that narrow (constrict) the blood vessels in the nasal membranes, thereby helping "shrink" swollen tissues and relieve congestion (e.g., decongestants); and
  • Drugs that reduce mucous production by blocking the nerve supply to the mucous glands (e.g., anticholinergics).

What are antihistamines?

Antihistamines are one of the most commonly used OTC and prescribed medications. They are beneficial for nasal and eye allergies, eczema, and hives but tend not to be effective in asthma.

Antihistamine is a combination of two words. "Anti-" means against, and "histamine" is a naturally occurring chemical that is released by the mast cells.

How do antihistamines work?

Human cells have three different types of histamine receptors (H1, H2, and H3). Histamine works by attaching itself to these receptors on the surface of cells and thereby causing its effects. It is mainly through the H1 receptors that histamine causes symptoms of allergy. Antihistamines act by attaching to these same H1 receptor sites, thereby preventing histamine from binding to them. This action prevents the histamine from causing allergic symptoms.

Histamines can cause swelling, sneezing, itching (nose, throat, roof of mouth), and a runny nose through the nostrils or down the back of the throat (post-nasal drip). Antihistamines are effective in treating the sneezing, running, and itching. They usually begin working between 30 to 60 minutes after being taken. However, histamine is only one of the many chemicals involved in the allergic reaction, which explains why relief from antihistamines is usually only partial.

Allergy Fact

Bovet and Straub at the Pasteur Institute discovered the first antihistamine in 1937. It was too weak, however, and caused many side effects. In 1942, phenobenzamin (Antegan) was the first antihistamine used to treat allergies. Within a few years, diphenhydramine (Benadryl) and tripelennamine (PBZ) were formulated.

What are first generation antihistamines (OTCs)?

Many of the older antihistamines are now available OTC. Many different preparations are available, and are derived from six separate chemical classes. Although these inexpensive OTC drugs are helpful in controlling milder symptoms, they also cause various side effects. Drowsiness and reduced mental alertness are particularly common (seen in up to 50% of those taking the medications). Cells that line the blood vessels in the brain regulate which chemicals can enter the brain. These cells are referred to as the blood brain barrier. The reason these drugs induce sleepiness is that they are able to cross the blood brain barrier.

Table I: Common First Generation Antihistamines

Generic Name Brand Name
diphenhydramine Benadryl
chlorpheniramine Chlortimeton, Allerest
clemastine fumarate Tavist
dexbrompheniramine Drixoral
Allergy Alert

If you ask your pharmacist for the generic version of your doctor's brand name suggestion, you may well get a different preparation. Check that the generic name is the same as the one your doctor recommended.

What are second generation antihistamines (prescription)?

The newer antihistamines are available by prescription only and are often referred to as "non-sedating." In general, this group of antihistamines is more expensive, has a slower onset of action, is longer acting, and induces less sleepiness. Even some of these can be slightly sedating (see Table II).

Allergy Alert

Two of the earlier second generation antihistamines, Seldane (terfenadine) and Hismanal (astemizole), were found to have unacceptable heart side effects and are no longer available on the market.

Table II: Second Generation Antihistamines

Generic Name Brand Name Usual Dosage
loratadine (non-sedating) Claritin tablet/redi-tab 10mg, Claritin syrup 5mg/tsp 10mg once per day
fexofenadine (non-sedating) Allegra capsule 60mg 60mg twice per day
cetirizine (slightly sedating) Zyrtec tablet 5mg or 10mg, Zyrtec syrup 5mg/tsp 10mg once per day
azelastine (slightly sedating) Astelin Nasal Spray Two sprays in each nostril two times per day

Antihistamines perform best when taken regularly or before an allergic reaction begins. The second generation antihistamines may take up to an hour or more to become effective. They should be taken well before an expected allergic exposure, such as a visit to a friend who has a cat.

What are common side effects of antihistamines?

Since the first generation antihistamines can penetrate the brain tissue, they generally cause more side effects than the second generation drugs, which usually cannot enter the central nervous system. Drowsiness is the most noticeable side effect, but this is sometimes desirable. For example, it may be useful when nighttime symptoms prevent restful sleep. During the day, however, this effect can cause problems.

Allergy Alert

Be cautious about driving a car or operating a machine when using OTC antihistamines. Do not take any tranquilizers or drink alcohol along with these drugs. The combination may promote more drowsiness. Also, check with your doctor before taking an antihistamine if you have glaucoma or thyroid, heart, or prostate problems.

The first generation antihistamines may also cause troublesome anticholinergic effects such as heart palpitations, difficulty urinating, constipation, dry mouth, and nervousness. These side effects usually occur when the medication is taken at higher than recommended doses.

The second generation of antihistamines currently on the market has few, if any, significant side effects at the recommended doses.

Allergy Assist

Antihistamines may be used for nasal symptoms in patients with asthma. It was previously thought that these drugs would dry up the airways in the patient's bronchial tubes and aggravate the asthma. However, there is no good evidence supporting this notion. Additionally, as you will learn, improving nasal symptoms may benefit patients with asthma.

What are decongestants?

Nasal stuffiness or congestion occurs as a result of swelling of the nasal membranes. Histamine opens the blood vessels and encourages fluid leakage from them, thereby causing the tissues to become "congested." This reaction reduces the space inside the nose through which we breathe and results in the typical "blocked" or stuffy nose. While antihistamines can control many symptoms of allergic rhinitis, they are not very helpful for treating nasal congestion once it has already occurred. At this point, decongestants can be a very useful addition.

How do decongestants work?

Decongestants act on a receptor on the blood vessels. The blood vessels thereby shrink, which in turn reduces the blood flow to the area and lessens the leakage of fluid into the tissues. The result is a nasal passage that feels more "open." It is important to remember that decongestants do NOT help with an itchy, sneezing, and runny nose.

Two forms of decongestants, oral and topical, are currently available. They are probably equally effective, although the topical nasal sprays or drops work more quickly (a few minutes compared to thirty minutes). Most preparations are OTC and are relatively inexpensive. As we will see later, decongestants are frequently combined with antihistamines and are sometimes combined with mucous thinners (mucolytics).

Table III: Common Decongestants

Generic Name Brand Name
pseudoephedrine (oral: liquid, tablets) Sudafed (Novafed)
phenylephrine (topical: drops, spray) Neosynephrine
oxymetolazone (topical: drops, spray) Afrin

When should I use topical decongestants?

The best use for topical decongestants, the nose drops and sprays, is for the quick, temporary relief of nasal stuffiness due to either allergic or non-allergic causes. They are helpful for relieving congestion in the Eustachian tubes, which equalize pressure between the inner ear and the nasopharynx. Decongestants are frequently used, therefore, before air flights to prevent ear symptoms during flight. In this regard, they may also be useful in treating ear infections. It is important, however, not to use these topical agents for longer than 3 to 5 days, since this may cause rebound congestion. Also, be careful to follow the daily use instructions - some decongestants need to be taken only twice a day while others may need to be used 3 to 4 times a day.

Allergy Fact

Nasal decongestants are effective in opening the entrances to the sinus cavities. This is particularly helpful in treating sinusitis and relieving sinus pressure.

The oral form of decongestants is the preferred choice for most cases of nasal congestion, particularly when you expect to use them for more than 3 to 5 days. They can also be taken for Eustachian tube blockage, infected ears, and sinusitis. Oral decongestants rarely cause rebound nasal congestion even if taken for long periods.

What are side effects of decongestants?

Topical sprays sometimes cause burning or dryness in the nose. The most well known side effect of topical decongestants is rebound nasal congestion. The longer you use the spray, the less effective it becomes and the more you find you need to use it in order to obtain the desired effect (virtually an addictive quality if used excessively). After prolonged use, the spray begins to cause more congestion than it relieves. The only way to break this cycle is to stop the medication. If the cycle is not broken, permanent changes can occur on the nasal membranes, which lead to a condition known as rhinitis medicamentosa. Rhinitis medicamentosa refers to an inflammation in the nose that is caused by the use of medications. Symptoms include severe stuffiness, burning, bleeding, and dryness of the nose.

 

Side effects from oral decongestants are more common and potentially more dangerous. They can stimulate the nervous system causing palpitations, insomnia, nervousness, and irritability. Some people may have trouble with urination and a decreased appetite. Although frequently mentioned, high blood pressure is not commonly caused or worsened by these drugs. If you have any concerns regarding the side effects of these drugs, discuss them with your doctor.

What about combination antihistamine/decongestant preparations?

Pharmacy shelves are packed with these preparations. They are useful for runny, itchy, and stuffy noses and are available OTC or by prescription. The liquid preparations are convenient for children as well as the elderly who may need a lesser dosage than is available in tablet forms. 12- and 24-hour preparations are available to make taking the medications more practical. Interestingly, the stimulant effect of the decongestant may counteract the drowsiness effect of the antihistamine and make the combination well tolerated.

Allergy Fact

Six of the top ten highest selling nonprescription medications (in 1990) were Dimetapp, Benadryl, Actifed, Drixoral, Comtrex, and Chlortrimeton. OTC antihistamine sales exceed $500 million per year and up to $2 billion per year when antihistamine-decongestant combinations are included.

Table IV: Common Antihistamine/Decongestant Preparations

Generation Brand Name

R = Rapid
Release

S = Sustained Release

Antihistamine Decongestant
First Bromfed Tabs R Brompheniramine 4mg Pseudoephedrine 60mg
Deconamine Tabs R Chlorpheniramine 4mg Pseudoephedrine 60mg
Rondec Tabs R Carbinoxamine 4mg Pseudoephedrine 60mg
Ornade S Chlorpheniramine 12mg Pseudoephedrine 120mg
Tavist D S Clemastine 1.34mg Pseudoephedrine 120mg
Trinalin Repetabs S Azatadine 1mg Pseudoephedrine 120mg

Second

Allegra D S Fexofenadine 60mg Pseudoephedrine 120mg
Claritin D 12-hour S Loratadine 5mg Pseudoephedrine 120mg
Claritin D 24-hour S Loratadine 10mg Pseudoephedrine 240mg
Semprex D S Acrivastine 8mg Pseudoephedrine 60mg

Two broad categories of decongestants are available. Rapid release products need to be taken 3 to 4 times a day and provide a lower dose of both the antihistamine and decongestant. These medicines help people who are more troubled by side effects but they are less practical than the sustained release preparations, which need to be taken only once or twice per day.

Allergy Alert

When you switch OTC antihistamine/decongestant combinations, please read the label. Make sure the ingredients and the dosages are different from the ones you used to take. Otherwise, you may be buying the same medication with a different name, color, shape, and price.

Table V: Nasal Symptoms and Medicine

Nasal Symptom Medicine
A Sneezing Antihistamine
Runny Nose
Itchy Nose/Throat
B Stuffy Nose Decongestant
C Combination of Symptoms
A + B
Antihistamine + Decongestant

Nasal Steroid Sprays

Steroids are naturally-occurring hormones that are produced by the adrenal glands. The corticosteroids have potent anti-inflammatory effects and are very effective in treating allergic inflammation in the nose. They are a "controller" type medication and work best when used on a regular "preventative" basis. With seasonal allergies, daily use of these sprays should begin 1 to 2 weeks before the allergy season and continue throughout the season. In year round or perennial allergic rhinitis, particularly if unresponsive to treatments, daily use of intranasal steroids has been found very effective in controlling symptoms, particularly nasal congestion. The addition of antihistamines to this nasal spray will likely give even better results.

Nasal steroids may also help improve the sense of smell, which is frequently diminished in allergic rhinitis. The medication may work by reducing swelling high up in the nose, where the area for smell is located. Decreasing the swelling allows more air (containing the odors) to reach the nerves that are responsible for the sense of smell.

Allergy Assist

Bag-like collections of fluid in the nasal membranes, called nasal polyps, are not uncommonly found in allergic rhinitis. Nasal steroids are helpful in shrinking nasal polyps and in preventing them from recurring.

Nasal steroids are available in two forms, aerosol and a spray pump (aqueous). The aerosol form resembles an asthma spray that delivers a predetermined dose of "dry" medication when activated. The more commonly used pump delivers a "water-based" spray, which may provide some moisturizing and soothing effect as well as an anti- inflammatory action. Patients who feel that the drip in their nose and throat increases when using the spray form may prefer the aerosol. In contrast, the spray is favored if the aerosol causes irritation or excessive drying of the nasal membranes.

Allergy Fact

In 1960, the first nasal steroid spray, Decadron Turbinaire, was introduced in the United States. Although very effective, too much of the drug was absorbed into the bloodstream, which resulted in side effects and limited its use. A different medication, Beclomethasone, was initially marketed in the 1970s and has been well tolerated.

Table VI: Common Intranasal Steroids (See Appendix.)

Generic Name Brand Name
beclomethasone Beconase, Vancenase (pump, aerosol)
flunisolide Nasarel, Nasalide (pump)
triamcinolone Nasacort, Nasacort AQ (pump, aerosol)
budesonide Rhinocort (aerosol)
fluticasone Flonase (pump)
mometasone Nasonex (pump)

The latter of these intranasal steroids - Rhinocort, Flonase, and Nasonex - are faster acting and more potent than the other nasal steroids, with no difference in side effects.

 

The safety record of nasal steroids at the recommended dosages is excellent. Several studies conducted in the U.S., Canada, and Europe have documented the lack of significant systemic (general body) side effects. The common side effects occur locally in the nose, such as burning, stinging, dryness, and sneezing, and are usually reported with the use of dry aerosol sprays. Less common effects include headache and mild nasal bleeding. The latter can be avoided by good spray technique. Shallow nasal ulcers are rare and can also be avoided by the use of good technique.

Corticosteroids are occasionally prescribed orally for a few days in cases of severe allergic rhinitis with almost total obstruction of the nasal passages. In these cases, antihistamines, decongestants, and certainly nasal sprays are not likely to help. After the nasal passages have opened, however, the nasal sprays can be used to prevent further swelling.

Other Nasal Sprays That Might Help

Ipratropium Bromide Spray (Atrovent)

Ipratropium bromide blocks the effects of acetylcholine, which is a chemical that, among other actions, signals the mucous glands in the nose to produce mucous. Allergic reactions can trigger excessive acetylcholine activity on the mucous glands. Ipratropium bromide occupies the same receptor on the glands as does acetylcholine and in this way reduces mucous secretion. You see, the ipratropium bromide that replaces acetylcholine on the receptor does not stimulate mucus secretion.

Ipratropium Bromide is available as a spray pump and comes in two strengths (0.03% and 0.06%). It is only effective for runny noses and can literally "turn off the faucet." The drug does not help itchy or stuffy noses and does not usually take the place of an intranasal steroid, but rather is used along with it. Typically, two sprays 3 to 4 times per day in each nostril are required to control symptoms. Once improvement is seen, the dose can often be lowered to one spray 3 to 4 times per day or two sprays 2 times per day.

Side effects of ipratropium bromide are infrequent but include dry nose, nasal irritation, and nose bleeding. If accidentally sprayed into the eyes, the drug may cause temporary blurred vision.

Allergy Assist

Ipratropium bromide nasal spray can dry up mucous, regardless of the cause. The spray may be effective in non- allergic rhinitis and even the common cold (usually at the higher 0.06% dose).

Cromolyn Sodium Nasal Spray (Nasalcrom)

Cromolyn works to reduce nasal inflammation without the use of steroids. It acts on mast cells to stabilize them, thereby preventing the release of histamine and other mediators. Since cromolyn is strictly a "controller" medication, it must be taken before allergic exposure, usually at least 2 weeks prior, due to its slow onset of effectiveness. The drug tends to be more effective in younger people with higher levels of IgE. It is given at doses of one to two sprays in each nostril 4 times per day. Cromolyn appears to be helpful in reducing runny nose, sneezing, and congestion in milder cases, but may not be effective at all in more severe cases. The medicine became available OTC in 1997. It is a particularly well tolerated medication with minimal side effects (usually sneezing, nasal irritation, or stinging. Rare cases of nasal bleeding or residual bad taste are reported.) There are no systemic, or body-wide, side effects.

 

Allergy Assist

Cromolyn nasal spray is safe for pregnancy, lactation, and children under the age of 6 years old.

Tips for Proper Use of Nasal Sprays

Using a good technique in applying nasal sprays will help you achieve the maximum benefits from the medications and avoid certain side effects, such as nasal bleeding. The following are guidelines for proper spray technique:

  • Clear your nasal passages with gentle nose blowing or a nasal decongestant for a few days when starting nasal steroids.
  • Shake the container.
  • Place one finger over one nostril to close it off.
  • Place the tip of the spray into the open nostril pointing away from the nasal septum (midline) and direct the spray straight back, not up into the tip of your nose.
  • Activate the spray, sniffing in gently and deeply as you do so.
  • Exhale through the mouth.
  • Repeat these steps for the other nostril.
  • Never "double" spray: always spray one nostril at a time and alternate nostrils each time.
Nasal Allergies At A Glance
  • Nasal allergy is an inflammatory reaction to house dust mites, mold, animal hair, and pollens.
  • Take antihistamines for sneezing, runny nose, itchy nose and throat.
  • Take decongestants for nasal congestion only.
  • Anticholinergic medicine such as Ipratropium Bromide may help with intractable runny noses.
  • Nasal steroids are safe and effective on a runny, itchy, and particularly stuffy nose.
  • Combination of antihistamine, decongestant, and steroid inhalers are a good choice for moderate or severe hay fever.
  • Topical nasal decongestant should be limited to use for 3 to 5 days maximum.


Allergy Shots

 

View Slideshow Pictures

 

10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
Nasal Allergy Relief Slideshow Pictures Nasal Allergy Relief Slideshow Pictures
  • How often are allergy shots given?
  • How should I prepare for allergy shots?
  • What are possible side effects of allergy shots?
  • Are allergy shots effective for all allergies?
  • What do I do if I'm experiencing a reaction from an allergy shot?
  • Are there any new approaches to immunotherapy?

 

Allergy shots, also called "immunotherapy," are given to increase your tolerance to the substances (allergens) that provoke allergy symptoms. They usually are recommended for people who suffer from severe allergies or for those who have allergy symptoms more than 3 months each year. They do not cure allergies, but reduce your sensitivity to certain substances.

How Often Are Allergy Shots Given?

Allergy shots are given regularly (in the upper arm), with gradually increasing doses. When starting immunotherapy, you will need to go to your healthcare provider once or twice a week for several months. The dose is increased each time until the maintenance dose is reached. If the shots are effective, you will go to your healthcare provider every 2 to 4 weeks for 2 to 5 more years. You may become less sensitive to allergens during this time, and your allergy symptoms will become milder and may even go away completely.

How Should I Prepare for Allergy Shots?

For two hours before and after your appointment, do not exercise or engage in vigorous activity. Exercise may stimulate increased blood flow to the tissues and promote faster release of antigens into the bloodstream.

Tell your doctor about all the medications you are taking. Some medications, such as beta blockers, can interfere with the treatment and/or increase the risk of side effects. You may have to stop allergy shots if you are taking these medications.

Talk to your doctor about the safety of continuing the allergy shots if you are pregnant or planning to become pregnant.

What Should I Expect After Allergy Shots?

Usually, you will be monitored for about 30 minutes after receiving an allergy shot to make sure that you don't develop side effects such as itchy eyes, shortness of breath, runny nose, or tight throat. If you develop these symptoms after you leave the doctor's office, take an antihistamine and go back to your doctor's office or go to the nearest emergency room.

Redness, swelling, or irritation within one inch of the site of the injection is normal. These symptoms should go away within 4 to 8 hours after receiving the shot.

Are Allergy Shots Effective for All Allergies?

The effectiveness of immunotherapy varies depending on the severity of a person's allergies and the number of substances to which the person is allergic. In general, however, immunotherapy is effective for allergies to stinging insects, a variety of pollens and dust mites, as well as for allergic asthma. It is also effective for molds and pet dander. Immunotherapy is not proven to be effective for hives or food allergies.

When Should I Call My Doctor?

After receiving your allergy shot, call your doctor and go to the nearest emergency room if you develop shortness of breath, tight throat, or any other symptoms of concern.

Beyond Allergy Shots: New Approaches to Immunotherapy

In addition to the traditional allergy shots, several new immunotherapy procedures have been proposed, including:

  • Rush immunotherapy: This approach involves a more rapid, or rushed, build-up to the maintenance dose of extract. During the initial phase of treatment, increasing doses of allergen are given every few hours rather than every few days or weeks. There is a greater risk of a body-wide reaction with this approach, so rush immunotherapy generally is done in a hospital under close medical supervision. In some cases, pre-treatment with medications can reduce the risk of an allergic reaction during rush immunotherapy.
  • Oral immunotherapy: Oral, or sublingual-swallow, immunotherapy works in the same way as allergy shots by giving increasing doses of allergen to gradually build up a person's tolerance. The difference with oral immunotherapy is the allergen extract is given as drops, usually placed under the tongue and then swallowed, rather than through injections. This type of immunotherapy has been shown to be helpful in a select patient population. However, formulations for sublingual-swallow use are not available in the United States, nor has sublingual administration received approval by the U.S. Food and Drug Administration.
  • Intranasal immunotherapy: Controlled, well-designed studies have shown intranasal administration of grass, birch tree, and house dust mite allergen extracts was effective at reducing nasal symptoms of rhinitis. Local irritation to the nasal mucosa was the main side effect. However, the effect of nasal administration may not have the longer lasting benefits that have been associated with traditional immunotherapy. Currently, intranasal immunotherapy is not used in the United States.


Drug Allergies

 

View Slideshow Pictures

 

10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
Nasal Allergy Relief Slideshow Pictures Nasal Allergy Relief Slideshow Pictures
  • Why do some medications cause allergic reactions?
  • What are the symptoms of drug allergy?
  • Which drug allergies are most common?
  • How are drug allergies diagnosed?
  • How are drug allergies treated?
  • How can I be prepared if I have a drug allergy?
  • Find a local Asthma & Allergy Specialist in your town

Allergies: Allergies to Medications

Many drugs can cause adverse side effects, and certain medicines can trigger allergic reactions. In an allergic reaction, the immune system mistakenly responds to a drug by creating an immune response against it. The immune system recognizes the drug as a foreign substance and the body produces certain chemicals, such as large amounts of histamine in an attempt to expel the drug from the body.

 

What Are the Symptoms of Drug Allergy?

Symptoms can range from mild to life-threatening. Even in people who aren't allergic, many drugs can cause irritation, such as an upset stomach. But during an allergic reaction, the release of histamine can cause symptoms like hives, skin rash, itchy skin or eyes, congestion, and swelling in the mouth and throat.

A more severe reaction may include difficulty breathing, blueness of the skin, dizziness, fainting, anxiety, confusion, rapid pulse, nausea, diarrhea, and abdominal problems.

 

Which Drug Allergies Are Most Common?

The most common drug associated with allergies is penicillin. Other antibiotics similar to penicillin can also trigger allergic reactions.

Other drugs commonly found to cause reactions include sulfa drugs, barbiturates, anticonvulsants, insulin, and iodine (found in many X-ray contrast dyes).

 

How Are Drug Allergies Diagnosed?

A doctor diagnoses a drug allergy by carefully reviewing your medical history and symptoms. If your doctor suspects that you are allergic to an antibiotic such as penicillin, he or she may do a skin test to confirm it. However, skin testing does not work for all drugs, and in some cases it could be dangerous. If you have had a severe, life-threatening reaction to a particular drug, your doctor will simply rule out that drug as a treatment option for you. Conducting an allergy test to determine if the initial reaction was a "true" allergic response isn't worth the risk.

How Are Drug Allergies Treated?

The primary goal when treating drug allergies is symptom relief. Symptoms such as rash, hives, and itching can often be controlled with antihistamines, and occasionally corticosteroids.

For coughing and lung congestion, drugs called bronchodilators may be prescribed to widen the airways. For more serious anaphylactic symptoms -- life-threatening reactions including difficulty breathing or loss of consciousness -- epinephrine may be given.

Occasionally, desensitization is used for penicillin allergy. This technique decreases your body's sensitivity to particular allergy-causing agents. Tiny amounts of penicillin are injected periodically in increasingly larger amounts until your immune system learns to tolerate the drug.

If you are severely allergic to certain antibiotics, there are alternative antibiotics your doctor can prescribe.

 

How Can I Be Prepared if I Have a Drug Allergy?

If you have a drug allergy, you should always inform your healthcare provider before undergoing any type of treatment, including dental care. It is also a good idea to wear a MedicAlert bracelet or pendant, or carry a card that identifies your drug allergy. In cases of emergency, it could save your life.


Lactose Intolerance
(Lactase Deficiency)

 

Take the Tummy Trouble Digestive Quiz

 

Take the Tummy Trouble Digestive Quiz Take the Tummy Trouble Digestive Quiz
Digestive Disease Myths Slideshow Pictures Digestive Disease Myths Slideshow Pictures
Diverticulitis (Diverticulosis) Slideshow Pictures Diverticulitis (Diverticulosis) Slideshow Pictures

Medical Author: Jay W. Marks, MD
Medical Editor: Bhupinder Anand, MD Professor, Department of Internal Medicine, Division of Gastroenterology, Baylor University College of Medicine

  • What is lactose intolerance?
  • What causes lactose intolerance?
  • What are the symptoms of lactose intolerance?
  • How are lactase deficiency and lactose intolerance diagnosed?
  • Elimination diet
  • Milk challenge
  • Breath test
  • Blood glucose test
  • Stool acidity test

     

  • Intestinal biopsy
  • What are the sources of lactose in the diet?
  • How is lactose intolerance treated?
  • Dietary changes
  • Lactase enzyme
  • Adaptation
  • Calcium and vitamin D supplements
  • What are the long-term consequences of lactose intolerance?
  • What is new in lactose intolerance?
  • Lactose Intolerance At A Glance
  • Related lactose intolerance article:
    Lactose Intolerance - on eMedicineHealth
  • Patient Discussions: Lactose Intolerance - Causes
  • Patient Discussions: Lactose Intolerance - Symptoms at Onset of Disease
  • Find a local Gastroenterologist in your town

What is lactose intolerance?

Lactose intolerance is the inability to digest and absorb lactose (the sugar in milk) that results in gastrointestinal symptoms when milk or food products containing milk are consumed.

What causes lactose intolerance?

 

Lactose is a large sugar molecule that is made up of two smaller sugars, glucose and galactose. In order for lactose to be absorbed from the intestine and into the body, it must first be split into glucose and galactose. The glucose and galactose are then absorbed by the cells lining the small intestine. The enzyme that splits lactose into glucose and galactose is called lactase, and it is located on the surface of the cells lining the small intestine.

Lactose intolerance is caused by reduced or absent activity of lactase that prevents the splitting of lactose (lactase deficiency). Lactase deficiency may occur for one of three reasons, congenital, secondary or developmental.

Congenital causes of lactose intolerance

Lactase deficiency may occur because of a congenital absence (absent from birth) of lactase due to a mutation in the gene that is responsible for producing lactase. This is a very rare cause of lactase deficiency, and the symptoms of this type of lactase deficiency begin shortly after birth.

Secondary causes of lactose intolerance

Another cause of lactase deficiency is secondary lactase deficiency. This type of deficiency is due to diseases that destroy the lining of the small intestine along with the lactase. An example of such a disease is celiac sprue.

Developmental causes of lactose intolerance

The most common cause of lactase deficiency is a decrease in the amount of lactase that occurs after childhood and persists into adulthood, referred to as adult-type hypolactasia. This decrease in lactase is genetically programmed, and the prevalence of this type of lactase deficiency in different ethnic groups is highly variable. Thus, in Asian populations it is almost 100%, among American Indians it is 80%, and in blacks it is 70%; however, in American Caucasians the prevalence of lactase deficiency is only 20%. In addition to variability in the prevalence of lactase deficiency, there also is variability in the age at which symptoms of lactose intolerance appear. Thus, in Asian populations, the symptoms of lactase deficiency (intolerance) occur around the age of 5, among Blacks and Mexican-Americans by the age of 10, and in the Finnish by age 20.

It is important to emphasize that lactase deficiency is not the same as lactose intolerance. Persons with milder deficiencies of lactase often have no symptoms after the ingestion of milk. For unclear reasons, even persons with moderate deficiencies of lactase may not have symptoms. A diagnosis of lactase deficiency is made when the amount of lactase in the intestine is reduced, but a diagnosis of lactose intolerance is made only when the reduced amount of lactase causes symptoms.

What are the symptoms of lactose intolerance?

The common primary symptoms of lactose intolerance are gastrointestinal include:

  • abdominal pain,
  • diarrhea, and
  • flatulence (passing gas).

Less common symptoms of lactose intolerance include:

  • abdominal bloating,
  • abdominal distention, and
  • nausea.

Unfortunately, these symptoms can be caused by several gastrointestinal conditions or diseases, so the presence of these symptoms is not very good at predicting whether a person has lactase deficiency or lactose intolerance.

Symptoms occur because the unabsorbed lactose passes through the small intestine and into the colon. In the colon, one type of normal bacterium contains lactase and is able to split the lactose and use the resulting glucose and galactose for its own purposes. Unfortunately, when they use the glucose and galactose, these bacteria also release hydrogen gas. Some of the gas is absorbed from the colon and into the body and is then expelled by the lungs in the breath. Most of the hydrogen, however, is used up in the colon by other bacteria. A small proportion of the hydrogen gas is expelled and is responsible for the increased flatulence (passing gas). Some people have an additional type of bacterium in their colons that changes the hydrogen gas into methane gas, and these people will excrete only methane or both hydrogen and methane gas in their breath and flatus.

Not all of the lactose that reaches the colon is split and used by colonic bacteria. The unsplit lactose in the colon draws water into the colon (by osmosis). This leads to loose, diarrheal stools.

The severity of the symptoms of lactose intolerance varies greatly from person to person. One reason for this variability is that people have different amounts of lactose in their diet; the more lactose in the diet, the more likely and severe the symptoms. Another reason for the variability is that people have differing severities of lactase deficiency, that is, they may have mild, moderate, or severe reduction in the amounts of lactase in their intestines. Thus, small amounts of lactose will cause major symptoms in severely lactase deficient people but only mild or no symptoms in mildly lactase deficient people. Finally, people may have different responses to the same amount of lactose reaching the colon. Whereas some may have mild or no symptoms, others may have moderate symptoms. The reason for this is not clear but may relate to differences in their intestinal bacteria.

How are lactase deficiency and lactose intolerance diagnosed?

Although there are several good ways to diagnose lactose intolerance, most people who consider themselves lactose intolerant have never been formally tested for intolerance. This is unfortunate because at least 20% of people who think they are lactose intolerant are not, and 20% of people who think they are not intolerant, in fact, are intolerant.

Why should so many people believe that they are lactose intolerant when they are not? This erroneous belief may be common for several reasons. People with unexplained (undiagnosed) gastrointestinal symptoms are looking for an explanation for their symptoms. Since lactose intolerance is a well-known condition, it provides these people with a ready (and welcome) explanation for their symptoms. Confirmation that lactose intolerance is present often is made subjectively and without careful correlation between ingestion of milk or milk products and symptoms. Extrapolating from data on the effect of placebo, it can be hypothesized that between 20 and 40 percent of people who think they feel better on stopping milk, in fact, are no better. Feeling better for them is analogous to a beneficial (positive) response to placebo.

Formal testing for lactose intolerance is valuable. Not only can testing confirm lactose intolerance and prompt the institution of a reduced or lactose-free diet, but it also can exclude lactose intolerance and direct attention to diagnosing other conditions and diseases that are responsible for the symptoms.

Elimination diet

Probably the most common way that people self-diagnose lactose intolerance is by an elimination diet, a diet that eliminates milk and milk products. There are several problems with this type of "testing."

  1. Milk products are so common in prepared foods from the supermarket or restaurant that it is likely that an elimination diet that is not rigorous (i.e., does not eliminate all milk-containing products) will still include substantial amounts of milk. Thus, persons with severe lactase deficiency attempting an elimination diet may be ingesting enough lactose to have symptoms and erroneously conclude that lactose intolerance is not responsible for the symptoms.
  2. People often make the assumption that they are lactose intolerant based on a short trial of elimination. A short trial may be adequate if symptoms are severe and occurring daily, but not if the symptoms are subtle and/or variable. In the latter case, an elimination diet may need to be continued for several weeks.
  3. Because symptoms of lactose intolerance are subjective and variable, there always is the possibility of a "placebo effect" in which people think they feel better eliminating milk when, in fact, they are no better. As discussed previously, with subjective symptoms such as those of lactose intolerance, a placebo effect might be expected to occur 20%-40% of the time.

If an elimination diet is to be used for diagnosing lactose intolerance, it should be a rigorous diet. A rigorous diet requires counseling by a dietician or reading a guide to a lactose-elimination diet. The diet also needs to be continued long enough to clearly evaluate whether or not symptoms are better. If there is doubt about improvement on the diet, particularly if symptoms normally fluctuate in intensity over weeks or months, repeated periods of lactose elimination should be tried until a firm conclusion can be drawn. Elimination of all milk products should eliminate symptoms completely if lactose intolerance alone is the cause of the symptoms.

Milk challenge

A milk challenge is a simpler way of diagnosing lactose intolerance than an elimination diet. A person fasts overnight and then drinks a glass of milk in the morning. Nothing further is eaten or drunk for 3-5 hours. If a person is lactose intolerant, the milk should produce symptoms within several hours of ingestion. If there are no symptoms or symptoms are substantially milder than the usual symptoms, it is unlikely that lactose intolerance is the cause of the symptoms. It is important that the milk that is used is fat-free in order to eliminate the possibility that fat in the milk is the cause of symptoms. It is not possible to eliminate the possibility that symptoms are due to milk allergy, a very different condition than lactose intolerance; however, this usually is not confusing since allergy to milk is rare and primarily occurs in infants and young children. (If milk allergy is a consideration, pure lactose can be used instead of milk.)

An important issue is the amount of milk required for the milk challenge.

  • If a person drinks several glasses of milk or ingests large amounts of milk-containing products in their normal diet, then a larger amount of milk should be used in the challenge, 8-16 ounces in an adult, equivalent to one or two large glasses of milk.
  • If the person being tested usually does not drink several glasses of milk or ingest larger quantities of milk-containing products, there may be a problem with using 8-16 ounces of milk for testing. These larger quantities of milk used for testing may cause symptoms, but the smaller amounts of milk or milk products that these persons ingest in their normal diet may not be enough to cause symptoms. Technically, they may be lactose intolerant when they are tested with larger amounts of milk, but lactose in their normal diet cannot be responsible for their usual symptoms.

Breath test

The hydrogen breath test is the most convenient and reliable test for lactase deficiency and lactose intolerance. For the breath test, pure lactose, usually 25 grams (the equivalent of 16 oz of milk), is ingested with water after an overnight fast. In persons who are lactose intolerant, the lactose that is not digested and absorbed in the small intestine reaches the colon where the bacteria split the lactose into glucose and galactose and produce hydrogen (and/or methane) gas. Small amounts of the hydrogen and methane are absorbed from the colon into the blood and then travel to the lungs where they are excreted in the breath. Samples of breath are collected every 10 or 15 minutes for 3-5 hours after ingestion of the lactose, and the samples are analyzed for hydrogen and/or methane. If hydrogen and/or methane are found in the breath, it means that the small intestine of the person was unable to digest and absorb all of the lactose. He or she is lactase deficient. The amount of hydrogen or methane excreted in the breath is roughly proportional to the degree of lactase deficiency, that is, the larger the amount of hydrogen and/or methane produced, the greater the deficiency. The amount of hydrogen and/or methane in the breath, however, is not proportional to the severity of the symptoms. In other words, a person who produces little hydrogen and/or methane may have more severe symptoms than a person who produces a large amount hydrogen and/or methane.

The breath test is the best test for determining lactase deficiency and lactose intolerance, but it has several weaknesses. The first is that it is a long, boring test. The second is that it suffers from the same issue as the milk challenge test with respect to the quantity of lactose that should be used. (See previous discussion.) Lastly, the breath test can be falsely abnormal when there is spread of bacteria from the colon into the small intestine, a condition called bacterial overgrowth of the small bowel. When overgrowth occurs, the bacteria that have moved up into the small intestine get to the lactose in the intestine before there has been enough time for the lactose to be digested and absorbed normally, and these bacteria produce hydrogen and/or methane. This may lead erroneously to a diagnosis of lactose intolerance. Other conditions also interfere with the breath test. Thus, diseases that markedly speed up transit of lactose through the small intestine prevent lactose from being fully digested and absorbed, leading to a misdiagnosis of lactose intolerance. Recent treatment with antibiotics can suppress colonic bacteria and their production of hydrogen or methane and lead to a misdiagnosis of lactose tolerance. Fortunately, these latter conditions are uncommon and usually can be anticipated on the basis of a person's history or symptoms.

Blood glucose test

The blood glucose test is an older test for lactase deficiency and lactose intolerance. For the blood glucose test, lactose is ingested (usually 0.75 to 1.5 gm of lactose per kg of body weight) after an overnight fast, and serial blood samples are drawn and analyzed for glucose. If the level of blood glucose rises more than 25 mg/100ml, it means that the lactose has been split in the intestine and the resulting glucose has been absorbed into the blood. This implies that lactase levels are normal. Unfortunately, the blood glucose test, though simple in principle, requires the collection of multiple samples of blood. Moreover, the test has many real and potential problems, the most common of which is false positive tests, that is, an abnormal test in people who have normal lactase levels and no lactose intolerance. For these reasons, the blood glucose test is not often used.

Stool acidity test

The stool acidity test is a test for lactase deficiency in infants and young children. For the stool acidity test, the infant or child is given a small amount of lactose orally. Several consecutive stool samples then are tested for acidity. With a deficiency of lactase, unabsorbed lactose enters the colon and is split into glucose and galactose. Some of the glucose and galactose is broken down by the bacteria into acids, for example, lactic acid. Lactic acid turns the stool acidic. Therefore, a lactase deficient infant or child will develop an acidic stool following the test dose of lactose.

Despite the availability of the stool acidity test, the superiority of breath testing has led to modifications in the equipment for collecting breath samples that makes it easier to do breath testing in young children and even infants. As a result, the stool acidity test is not done frequently.

Intestinal biopsy

The most direct test for lactase deficiency is biopsy of the intestinal lining with measurement of lactase levels in the lining. The biopsy can be obtained by endoscopy or by special capsules that are passed through the mouth or nose and into the small intestine. The analysis of lactase levels in the biopsy requires specialized procedures that are not often available, and, as a result, lactase levels are not often measured except for research purposes.

What are the sources of lactose in the diet?

Although milk and foods made from milk are the only natural sources of lactose, lactose often is "hidden" in prepared foods to which it has been added. People with very low tolerance for lactose should know about the many food products that may contain lactose, even in small amounts. Food products that may contain lactose include:

  • bread and other baked goods;

     

  • processed breakfast cereals;

     

  • instant potatoes, soups, and breakfast drinks;

     

  • margarine;

     

  • lunch meats (except those that are kosher);

     

  • salad dressings;

     

  • candies and other snacks; and

     

  • mixes for pancakes, biscuits, and cookies.

Some products labeled nondairy, such as powdered coffee creamer and whipped toppings, also may include ingredients that are derived from milk and, therefore, contain lactose.

Smart shoppers learn to read food labels with care, looking not only for milk and lactose in the contents but also for such words as whey, curds, milk by-products, dry milk solids, and nonfat dry milk powder. If any of these are listed on a label, the item contains lactose.

In addition to food sources, lactose can be "hidden" in medicines. Lactose is used as the base for more than 20% of prescription drugs and about 6% of over-the-counter drugs. Many types of birth control pills, for example, contain lactose, as do some tablets used for stomach acid and gas. However, these products typically affect only people with severe lactose intolerance because they contain such small amounts of lactose.

How is lactose intolerance treated?

Dietary changes

The most obvious means of treating lactose intolerance is by reducing the amount of lactose in the diet. Fortunately, most people who are lactose intolerant can tolerate small or even moderate amounts of lactose. It often takes only elimination of the major milk-containing products to obtain sufficient relief from their symptoms. Thus, it may be necessary to eliminate only milk, yogurt, cottage cheese, and ice cream. Though yogurt contains large amounts of lactose, it often is well-tolerated by lactose intolerant people. This may be so because the bacteria used to make yogurt contain lactase, and the lactase is able to split some of the lactose during storage of the yogurt as well as after the yogurt is eaten (in the stomach and intestine). Yogurt also has been shown to empty more slowly from the stomach than an equivalent amount of milk. This allows more time for intestinal lactase to split the lactose in yogurt, and, at least theoretically, would result in less lactose reaching the colon.

Most supermarkets carry milk that has had the lactose already split by the addition of lactase. Substitutes for milk also are available, including soy and rice milk. Acidophilus-containing milk is not beneficial since it contains as much lactose as regular milk, and acidophilus bacteria do not split lactose.

For individuals who are intolerant to even small amounts of lactose, the dietary restrictions become more severe. Any purchased product containing milk must be avoided. It is especially important to eliminate prepared foods containing milk purchased from the supermarket and dishes from restaurants that have sauces.

Another means to reduce symptoms of lactose intolerance is to ingest any milk-containing foods during meals. Meals (particularly meals containing fat) reduce the rate at which the stomach empties into the small intestine. This reduces the rate at which lactose enters the small intestine and allows more time for the limited amount of lactase to split the lactose without being overwhelmed by the full load of lactose at once. Studies have shown that the absorption of lactose from whole milk, which contains fat, is greater than from non-fat milk, perhaps for this very reason. Nevertheless, the substitution of whole milk or yogurt for non-fat milk or yogurt does not seem to reduce the symptoms of lactose intolerance.

Lactase enzyme

Caplets or tablets of lactase are available to take with milk-containing foods.

Adaptation

Some people find that by slowly increasing the amount of milk or milk-containing products in their diets they are able to tolerate larger amounts of lactose without developing symptoms. This adaptation to increasing amounts of milk is not due to increases in lactase in the intestine. Adaptation probably results from alterations in the bacteria in the colon. Increasing amounts of lactose entering the colon change the colonic environment, for example, by increasing the acidity of the colon. These changes may alter the way in which the colonic bacteria handle lactose. For example, the bacteria may produce less gas. There also may be a reduction in the secretion of water and, therefore, less diarrhea.

Calcium and vitamin D supplements

Milk and milk-containing products are the best sources of dietary calcium, so it is no wonder that calcium deficiency is common among lactose intolerant persons. This increases the risk and severity of osteoporosis and the resulting bone fractures. It is important, therefore, for lactose intolerant persons to supplement their diets with calcium. A deficiency of vitamin D also causes disease of the bones and fractures. Milk is fortified with vitamin D and is a major source of vitamin D for many people. Although other sources of vitamin D can substitute for milk, it is a good idea for lactose-intolerant persons to take supplemental vitamin D to prevent vitamin D deficiency.

What are the long-term consequences of lactose intolerance?

The important long-term health consequence of lactose intolerance is calcium deficiency that leads to osteoporosis. Less commonly, vitamin D deficiency may occur and compound the bone disease. Both of these health issues can be prevented easily by calcium and vitamin D supplements. The real problem is that many lactose intolerant people who consciously or unconsciously avoid milk do not realize that they need supplements.

What is new in lactose intolerance?

It is now possible to test the DNA of individuals to make a diagnosis of lactase deficiency. This is likely to be an important research tool for studying lactase deficiency. It is still too early to know how helpful this sophisticated test will be in the clinical evaluation and treatment of patients. It is an expensive test. Moreover, the test is not very good at distinguishing between lactase deficiency and lactose intolerance since the symptoms of lactose intolerance vary in severity among individuals. The important question to answer is, does lactose cause symptoms, and not, whether an individual is lactase deficient.

In 1998, scientists were able to make lactose intolerant rats tolerant to lactose by transferring the gene for lactase to their intestinal lining cells. It is unlikely that this type of gene therapy will find much of an application in people. Nevertheless, it is a fascinating example of what science can accomplish.

Lactose Intolerance At A Glance
  • Lactose intolerance is an inability to digest lactose, the main sugar in milk, that gives rise to gastrointestinal symptoms.
  • Lactose intolerance is caused by a deficiency of the intestinal enzyme lactase that splits lactose into two smaller sugars, glucose and galactose, and allows lactose to be absorbed from the intestine.
  • The primary symptoms of lactose intolerance are diarrhea, flatulence (passing gas), and abdominal pain. Abdominal bloating, abdominal distention, and nausea also may occur.
  • Lactose intolerance can be diagnosed by eliminating lactose from the diet, milk challenge, breath test, blood glucose test, stool acidity test, and intestinal biopsy.
  • Lactose intolerance is treated with dietary changes, supplements of lactase enzyme, and adaptation to increasing amounts of milk.
  • Avoidance of milk and milk-containing products can lead to a dietary deficiency of calcium and vitamin D that, in turn, can lead to bone disease (osteoporosis).


Allergy Treatment Begins at Home

 

Causes of Fatigue Slideshow Pictures

 

Causes of Fatigue Slideshow Pictures Depression Tips for Exercise, Diet and Stress Reduction
How To Make A Healthy Home Slideshow Pictures How To Make A Healthy Home Slideshow Pictures
Bed Bugs Quiz Bed Bugs Quiz
  • Introduction
  • Cleaning and more cleaning: what really helps?
  • What are great techniques for mold patrol?
  • How can people with allergies ideally control the air quality and climate in their homes?
  • How can dust covers help?
  • What are carpet powders? Can they help?
  • What to do with the pets?
  • What do I do with those ghastly cockroaches?
  • Allergy Treatment At A Glance
  • Find a local Asthma & Allergy Specialist in your town

Introduction

Avoidance is always the best treatment for allergies regardless of which allergens are the triggers. Interestingly enough, the most effective, least expensive, and simplest options are not always followed. Many people choose medications or vaccinations instead, despite their drawbacks. Fortunately, there are lots of simple methods, both old and new, to help with avoidance. Remember, putting into practice any of these measures can only be helpful in managing your allergies.

The good news is that you really don't have to strip your house down to the bare bones to make it allergy proof. Thorough and regular cleaning generally makes a huge difference in keeping your house as mold and dust free as possible. Patients with asthma or allergic rhinitis that are due to dust mites, molds, or other indoor allergens can feel better by taking these simple measures:

  • Keep the home cool (between 68 and 72 degrees F);
  • Maintain a low humidity (between 40 and 50%); and
  • Make certain there is good ventilation.

When patients get started with the process of "allergy- proofing" their homes, one of two things usually happens. They either do nothing or "overdo it." Some patients become so overwhelmed with all the different methods of allergy- proofing that they simply do nothing. That's always a disappointing outcome, especially when the process is so straightforward and inexpensive. Just focusing on the basics of a routine and thorough cleaning and temperature and humidity reduction can lead to fewer symptoms and a vastly improved quality of life.

Sometimes, the opposite occurs. The allergy-proofing process becomes all consuming and inordinately expensive. Overpriced and often inefficient whole-house filtration devices are installed when simple cleaning and reduction of humidity and temperature would have been adequate. Clearly, there are situations in which extreme measures need to be undertaken. Before going down this path, however, it's best to consult with your doctor. Start with the easy things first.

The next section will describe the best steps to take in allergy-proofing your home. Always take a calculated approach, stepping up the process as needed for certain problems. First, we will focus on the best ways to clean and in the second part, on the available technologies.

Cleaning and More Cleaning: What Really Helps?

If you are going to undertake to thoroughly clean your home, it is best to ensure at the beginning that the techniques being used are the most effective. The tips discussed below will help you achieve the maximum benefit for all of your efforts.

Soap & Hot Water

Scientific studies of patients who are allergic to dust mites have shown that taking steps to minimize dust mite allergens in the bedroom leads to a decrease in allergic symptoms and medication requirements. Emphasis is placed on the bedroom since people spend at least one third of a 24 hour day there. It is also the room with the greatest number of dust mites.

New synthetic bedding materials are available that are equivalent to down for warmth but can withstand washing more easily because the fibers don't clump. The ideal water temperature for washing is at least 130 degrees F to completely kill the dust mites found throughout the bedding.

Allergy Alert

When the hot water heater is set to achieve a temperature of 130 degrees F, precautions must be taken to prevent scalding a child. For example, at bath time, always remain in the room with a child and make sure to always turn off the "hot" water faucet first and finish with the "cold" faucet.

The choice of bedding materials becomes important. They must be able to withstand the rigors of weekly hot water washing in order to kill the dust mites and remove accumulated allergens. Many bedding materials may be bulky, making them more difficult to wash. It may be easier to use several layers for warmth instead of bulky items for ease of washing. Since any type of blanket material can support dust mite growth, it is important to select one that can withstand repeated washings.

Vacuuming the Right Way

If the carpet can't be replaced by a solid surface such as linoleum or hardwood, then it must be cleaned thoroughly and frequently. Also remember to vacuum upholstered furniture, draperies, and other fabric items that cannot be washed, removed, or replaced. The trouble with vacuuming is that the allergenic dust mite and mold particles become airborne during the process. Dust mite particles can remain airborne for about 15 minutes and be redistributed throughout the home environment. Allergic persons clearly should not be doing the vacuuming and should also stay out of the area until the dust particles resettle. Dust mite particles also become airborne during bedding changes or the placement of dust covers on the mattress, box spring, and pillows. For severely allergic people, these tasks can lead to significant allergy and possible asthma attacks. Those affected by these allergies should definitely not perform these chores.

Allergy Alert

Allergic persons should not perform vacuuming tasks and should keep out of the immediate environment for at least 1 hour after the vacuuming has been completed. Damp dusting should then follow to catch any loose particles.

The vacuum cleaner collecting bag acts as the primary filter in most vacuum cleaning systems. A standard bag can be replaced with a high-filtration multi-layer bag and an exhaust filter can be added. These measures prevent the allergen particles from escaping and becoming airborne during the vacuuming process. Replacing the vacuum bags and adding exhaust filters are economical ways to increase the efficiency of an older vacuum. These bags and filters are easily obtained from allergy supply houses. The filters are available in 8" x 10" sheets that can be cut to size for any canister vacuum. Very expensive vacuum units with built-in HEPA systems (High Efficiency Particulate Air- filter) have been available for years. Now, more affordable brands of vacuums come equipped with HEPA filters and a removable canister that can be washed in the top rack of the dishwasher. This system eliminates the problem with vacuum bags. As the older generation of vacuums is phased out, this development should be quite helpful in allergy control. Whole-house vacuum systems, although quite expensive, are also helpful because the dirt collection system is located outside of the house, usually in the garage.

Hard Surfaces Are Easier to Clean

Dust mites, molds, animal danders, and insect debris are difficult to thoroughly clear from the environment. However, it really is easier and quicker to clean a hard surface such as wood, tile, vinyl, or leather than it is to clean all those nooks and crannies found in carpet, fabric, or other soft surfaces.

Allergy Assist

Replacing the carpet with a hard-surfaced floor can eliminate over 90% of dust mites. If you absolutely have to have carpet, get the kind that has a low pile.

 

The following is a list of suggestions for how to make allergy-proofing an easier task. Hopefully, these ideas will lead to other methods you can use to thoroughly clean and maintain your environment allergy free. Take it one step at a time and focus on the bedrooms first. If you plan on moving, pay close attention to steps that can be taken to allergy-proof prior to moving into the new house. It is much easier to put these ideas into action in the beginning than after everything is in place. It's really not as hard as it looks!

 

Cleaning Tips

  • Avoid ornate furniture. Plain, simple designs accumulate less dust. No open bookshelves; they are great dust-catchers.
  • Keep all clothes in drawers or closets, never lying about the room. Enclose wool clothes in plastic zipper bags. Avoid mothballs, insect sprays, tar paper, or camphor. Keep drawers and closet doors closed.
  • Remove as much clutter as possible to make cleaning easier. Place hard-to-clean items in closets, drawers, or display cabinets with glass doors.
  • When choosing furnishings, it is best to go with wood, leather, vinyl, or rubberized canvas furniture and avoid upholstered pieces. Upholstery easily traps allergens and is much harder to clean. You might try washable slipcovers on existing upholstered furniture.
  • Install wood, tile, or linoleum flooring. Limit throw rugs to those that can be easily cleaned in the washer. They should be able to withstand washing weekly.
  • Use allergen-proof encasings for pillows, mattresses, and box springs. Tape over zippers to help prevent leaks. Vacuum all casings frequently. Store nothing under the bed.
  • Use washable cotton or synthetic blankets, not fuzzy surfaced ones. Use easily laundered cotton bedspreads or coverlets; avoid chenille.
  • Install roll-up washable cotton or synthetic window shades. Avoid venetian blinds, mini-blinds, and pleated shades.

  • Use washable cotton or fiberglass curtains. Avoid draperies and decorative fabric window treatments!
  • Install central air conditioning or window units. Keep windows closed, especially during periods of high pollen counts and windy conditions. Grasses, weeds, and trees tend to pollinate during the early morning hours. Sleep with the windows closed.
  • Use Dacron or other synthetics for pillows. Avoid feathers or foam rubber, which traps moisture and promotes mold and dust mite growth.
  • Space heaters are preferred over hot air ducts. In homes with forced air heat, use filters or damp cheesecloth over inlets to reduce dust circulation. Change every two weeks. Consult your physician about air purifiers. Keep beds away from air vents.
  • Damp dusting using a dampened cloth or an oiled mop will minimize the distribution of dust through the air.

Baby's Room - Special Tips

It's a good idea to eliminate potential irritants and allergens from your baby's environment. Here's what you can do to help eliminate potential sources of allergens from your baby's world.

  • Wood or plastic chairs are best for baby's room.
  • Again, avoid all feather bedding.
  • Use dust-proof casings for all bedding.
  • Stuffed animals should never be placed in the crib and, if used, should be washable. Put most of the stuffed items in a closed chest or closet. Store them in a freezer bag when not in use.
  • When it comes to gifts for children, ask for books rather than stuffed animals. Keep the books in a bookcase with doors to help reduce allergens.
  • Humidifiers should be reserved for croup. They should not be used routinely since they increase the dust mite and mold counts. If a humidifier is required, the cool water variety is safer than a steam humidifier in terms of burns. Also, be sure to change the water daily if a humidifier is necessary.
  • Animal fur is a potential allergen. It's best to keep pets out of the baby's room.
  • Overhead mobiles and wall hangings collect dust!
  • Baby bumpers should be simple and washable. No ruffles or pleats.
  • Ruffled curtains and venetian blinds collect a lot of dust. Vertical blinds are preferable. If levelers or shutters are used, be sure to clean them weekly with a damp cloth.
  • The crib should be placed away from air vents.
  • A HEPA filter (High Efficiency Particulate Air-filter) can be placed under the crib. The filter will help to decrease airborne allergens such as pollens, mold spores, and animal danders.

What are great techniques for mold patrol?

Mold spores can pop up anywhere. There are lots of ways to deal with this persistent problem that are cost effective and really work. Dealing with mold requires elbow grease, patience, and mold know-how. Do not give up; the effort is well worth it.

Allergy Alert

Greenhouses, antique shops, saunas, sleeping bags, summer cottages and hotel rooms are sources of increased mold exposure. Automobile air conditioners may harbor mold.

Anti-mold Preparations

Numerous cleaning products specializing in mold control are available. The active ingredients in these products that are effective against molds are bleach and ammonia. So why should you pay a premium for anti-mold preparations when you can readily prepare the mixture at home for a fraction of the cost? As long as you are aware of the fabric fading effects and the potentially caustic nature of these cleaning materials, there should be no problems. Limited areas of mold collection (as occurs in the bathroom) can be cleaned with a bleach solution. An old toothbrush and bleach work wonders on the dark mildew that often collects between the tiles. If there is carpet in the bathroom (ideally there shouldn't be since this is a "moisture trap" for mold), be careful not to drip the bleach on the carpet! Regularly using a "squeegee" along with a bottle of dilute bleach will help keep the mold spores under control.

Shower curtains present a special problem for mold control. Once the curtain is stained with mold spots, it might be worth a wash and rinse cycle with bleach. Usually, however, by the time you can see dime-size deposits of mold on the plastic shower curtain, it's probably not worth the effort. At this point, it would be better to purchase a vinyl curtain with a mold inhibitor. (These are available for use in motel rooms.)

Larger areas, especially under the house, should be treated with either Orthocine, Captan's powder (8 oz in a gallon of water), or bleach (mix 1 cup of bleach to 1 gallon of water). These products are available in hardware stores. Using rubber gloves, scrub the affected areas and repeat the process in 2 hours.

For even more extensive molds under the house, buy a 5 lb. bag of Bordeaux mixture (mostly copper sulfate) from any regular nursery and mix it with 15 to 20 gallons of water in a large tank sprayer. Spray the areas under the house, the ground, and all wood thoroughly at least 3 to 4 times a year for the first several years.

If the Bordeaux mixture is unavailable or does not control the problem, Ziram can be used in a 1-2% spray solution. Mix 3 ounces of the concentrate to 1 gallon of water. Ziram can also be used in the home for walls and floors. When applied to some fabrics, it may produce a slightly yellow color. Protective clothing should always be used when spraying this fungicide. One application of Ziram is usually sufficient for mold control.

Allergy Alert

Caution: DO NOT STORE FUNGICIDES NEAR FIRE OR OPEN FLAMES. ALWAYS BE SURE THERE IS GOOD VENTILATION DURING USE SINCE MANY OF THESE SUBSTANCES ARE TOXIC!

Indoor Mold Control - Other Measures

  • Lower the humidity level in the house.
  • Use fans for proper ventilation.
  • Clean visible mold from walls and ceilings.
  • Keep firewood outside since the bark is covered with mold.
  • Add mold inhibitor to paint before applying if it will be used in a damp environment, especially on brick and cinderblock walls in a basement or shady areas.
  • Mold tends to grow in closets, as they tend to be dark and damp. Dry shoes and boots before storing. Consider a chemical moisture remover (desiccant) such as calcium carbonate flakes or crystals. One brand is Dri-Out Dome, which is readily available through allergy catalogs and home improvement stores.
  • Do not carpet the bathroom.
  • Mold grows in refrigerators. Keep them clean and defrosted. Remove spoiled food, preferably before it gets that way!
  • Correct seepage or flooding problems and remove water- damaged carpet.
  • Carpet and pad should not be laid on a concrete floor since this is a great place for moisture to accumulate, resulting in a flourishing population of dust mites and mold.
  • Remove moldy stored items from the basement and keep it clean.
Allergy Assist

Farmers, gardeners, bakers, brewers, florists, carpenters, mill workers, upholsterers, and paper hangers have an increased exposure to mold due to their occupations. Your allergist can offer specific recommendations for handling these work environments.

How can people with allergies ideally control the air quality and climate in their homes?

Controlling the air quality and climate of your home may sound daunting, but it is actually not that difficult to achieve and can lead to substantial benefits. Good maintenance of these systems can increase the benefits you will receive and prolong the life-span of these devices.

HEPA Filters

HEPA stands for High Efficiency Particulate Air-filter. These devices were developed during the Apollo era of space exploration. They can filter most substances from the air, down to 0.3 microns in size. (A micron is a unit of length equivalent to 1/1000 of a millimeter.) They are helpful in filtering pollen, mold spores, animal dander, and fumes.

 

Allergy Assist

HEPA filters aren't for dust mites. Dust mite allergens are heavy and fall to the ground quickly, thus avoiding being trapped by HEPA filters.

It is important to remember that you can not filter the world. In other words, you need to run these filters with the windows closed. The size of the room also needs to be taken into consideration when deciding what size HEPA filter to purchase.

HEPA filters have become increasingly available in many discount home improvement stores. Previously, these devices had been primarily available through allergy supply companies and catalogs at a premium price. Now, you can do some comparative shopping before you buy. Other factors to consider before buying include the required interval between changing filters, the ease of obtaining replacement filters, and warranties. One critical factor in the use of HEPA filters is the noise level generated. Many people stop operating the unit due to the "white noise" associated with the device. Make sure that you listen to the device before you purchase it. The good news is that the newer generation of filters is much quieter.

Another type of filter is the electrostatic filter. So far, these have not been shown to be as efficient as the HEPA filter.

An important point to make here is that HEPA filters are not the ultimate solution to the problem of indoor allergens. They can help to some degree but in no way do they replace cleaning, temperature and humidity reduction, clutter removal, and avoidance of allergens such as pet dander.

Dehumidifiers & Humidifiers

Remember, house mites require high humidity to thrive. Dehumidifying the air is easily accomplished with an air conditioner, but this is practical only in hot weather. The correct placement and use of fans and vents can help reduce humidity as can a dehumidifier machine. It pays to find a knowledgeable sales source that can help you determine the appropriate size machine needed for your individual home or office. Clearly, the most important point about a dehumidifier is that it must be kept scrupulously clean. Otherwise, molds will flourish in the collection chamber making your problem worse than it was in the first place. Dehumidifiers must be cleaned daily. Some models have automatic shut off mechanisms that keep the tank from overflowing and some have a continuous drainage system.

Humidity gauges are readily available at any hardware store. A range of 40-50% humidity is good. Humidity lower than 35% can make breathing uncomfortable for some people with asthma or other respiratory conditions. Generally speaking, low humidity is not the health problem that high humidity can be.

Humidifiers are rarely needed except for children with croup. In most parts of the country, the humidity seldom drops below 35% and the nostrils and airways provide natural moisture. However, it is true that in certain parts of the country, a well heated home can become overly dry.

Allergy Fact

Croup is a viral infection in small children that is characterized by a harsh, barking cough. The condition is frequently worse at night. One of the recommended treatments is mist or steam, which is best provided by a cool air humidifier. Vaporizers should be avoided due to the risk of burns.

As previously noted, some central hot-air systems may include built-in humidifiers that can make the air more comfortable to breathe. However, there are definite problems with this type of system. Not only can these units blow mold spores and dust all through the air, but keeping these systems mold and bacteria free is extremely difficult.

Stand-alone humidifiers are available and are frequently used in homes with antiques or fine art that could be damaged from excessive dryness. They are often recommended for people with respiratory problems and eczema, which can be worsened by dryness. The truth is, though, that humidifiers tend to cause more problems than they solve. They should be used only sparingly, as their health benefits are primarily limited to infants or young children with croup.

The most frequently used stand alone unit is the evaporative humidifier. This system uses a wick or pad to absorb water from a reservoir. A fan then disperses the water vapor through the air. This method can cause bacterial counts in the air to skyrocket, leading to "humidifier fever," a flu-like infection of the respiratory tract.

Although ultrasonic humidifiers kill the bacteria, they also spray parts of the dead microorganisms into the air along with minerals that then deposit on surfaces throughout homes. A fine white dust on furniture evidences these mineral deposits. Generally, the ultrasonic models are no longer distributed but these devices are kept for years, so be sure to check what type of model you might own. A newer type of device is a vibratory humidifier that doesn't cause mineral deposits. All humidifiers should be used sparingly and MUST be cleaned after each use to prevent the rapid growth of bacteria and mold spores. Just by lowering the temperature of the home during the winter, the air will contain more moisture and the need for humidifiers will be minimized.

Air Conditioning & Heating Systems

Air conditioners are critical in filtering summertime air for patients allergic to molds and pollens. They also function as excellent dehumidifiers, thus limiting the growth of dust mites and molds. Another unexpected benefit is that the airflow discourages cockroaches since they prefer non-ventilated spaces.

Filters on both central and window units require frequent changing and or cleaning to remain efficient and prevent mold growth.

Separate room or area filtration units are more effective than whole house filtration units that are installed on central air systems. Claims that an entire house can be adequately filtered with just one unit are false. A HEPA filter can only cover a certain number of cubic feet and separate units need to be installed throughout the system.

Central air-conditioning and heating systems may also come with electrostatic filters that catch smaller particles than regular filters. The filters charge the particles in the air as they pass through the filter. The charged particles are then trapped by an oppositely charged plate in the unit. These devices must be cleaned frequently as well.

Allergy Alert

A concern about electrostatic filters has been ozone production, which can make asthma worse. This hazard has been reduced by the addition of charcoal filters.

Unfortunately, it is not clear whether the special filters available for home heating and air-conditioning units are completely effective. Be sure to inquire about the particle size that the filter is guaranteed to trap. A minimum of 5 microns is recommended. At this point, it appears that of the two options, HEPA filtration is superior.

Another option is the placement of individual filters over the outlet ducts themselves. These filters should be cleaned weekly and replaced as necessary. They are readily available from most allergy supply stores and catalogs and home hardware stores.

Some forced-air heating systems come with built-in humidifiers. This feature can backfire because dust particles are stirred up by the hot air and mold can flourish in the humidifier itself. Cleaning these units is of the utmost importance, but this can be a cumbersome task. If mold is a problem, it's probably best to have the humidifier removed.

Options apart from forced air systems include space heaters and radiant-heat systems. These two methods of heating are advantageous in that allergens and irritants are not distributed throughout the home environment as they are with forced air systems.

What are carpet powders? Can they help?

By this point we all know how important it is to remove the carpets, especially in the bedroom. Sometimes though, this just is not practical. Perhaps you are renting your home or apartment or maybe you just had the carpet replaced before you became aware of your dust mite allergy. Don't worry, there are ways around this.

One option is tannic acid (3% solution). Although the acid doesn't kill the dust mites, it does destroy the mite allergens. The solution can be easily sprayed on troublesome surfaces and is fast acting. It may, however, cause staining of carpets and upholstery. On a positive note, tannic acid may inactivate cat allergens, but this requires frequent application. Unfortunately, tannic acid has a temporary effect at best.

Another option is an "acaracide," which comes as a powder or spray that actually kills the dust mites and decreases the antigen levels. This product is available through allergy supply companies, but remains unavailable in Canada.

Allergy Alert

The presence of a smoker in the home will sabotage the best of all possible treatment programs for allergies and asthma. If you, your spouse or partner, or your child have chronic allergies or asthma problems, don't smoke and don't allow smoking in the home. Smoking may be the reason why allergy and asthma symptoms are persisting despite an otherwise thorough allergy control and medication treatment program. Children who are exposed to cigarette smoke are at a 50% increased risk of developing asthma. There are no excuses and "smoking outside" is not good enough. If you smoke, quit now. It's terrible for you and for everyone who lives with you.

What to do with the pets?

This is frequently a challenging issue for both doctors and allergy sufferers. Common sense and emotion often collide and differences of opinion amongst family members may complicate the problem. In order of their effectiveness, the recommended control measures for a significantly allergic or asthmatic individual are:

  • Find another home for the pet.
  • Keep the pet outdoors at all times. Remember, though, that the allergens will come into your home on your clothes.
  • Keep the pet out of the allergic person's bedroom at all times.

Even after you have found a new home for your pet, animal allergens may still persist in your home for many months in the typical reservoirs, carpeting, upholstery, and mattresses. Repeated vacuuming, steam cleaning, and applications of 3% tannic acid solution will help neutralize the remaining allergens.

If parting with your pet is unacceptable, the following are additional tips for managing the home environment.

  • When the pet is indoors, keep it in a room with few allergy reservoirs, such as the kitchen.
  • Provide your cat or dog with its own bed.
  • Use a HEPA filter in the bedroom and a portable room heater if needed. Seal off the room air ducts.
  • Wear a mask when handling the litter box, or even better, have a non-allergic family member do it.
  • Vacuum with a double filter or a HEPA filter.
  • Wash the cat weekly to help remove surface allergens.

 

Allergy Assist

Kittens take to regular bathing better than do older cats. Start slowly with a few drops of tepid water (soap is not necessary) on its fur and then progress to a full rinse. Reward the cat with treats - this might help.

What do I do with those ghastly cockroaches?

Elimination of cockroaches is best accomplished by using a professional exterminator. However, this is only the first step. After the cockroaches have been eliminated, the areas they inhabited must be thoroughly cleaned since their residual debris is highly allergenic. Entry points should be sealed to prevent re-infestation. Use covered trash bins and empty then frequently. Do not store cardboard boxes, newspapers, grocery bags, or empty cans and bottles in your home as they can serve as breeding areas.

 

Effectiveness of Avoidance Measures

Allergen - Dust Mites

  • Most Effective
    • Dust Covers
    • Weekly hot water washing of bedding
    • Carpet Removal
    • Keep rooms cool and dry
  • Possibly Effective
    • Chemical treatment of carpet
  • Least Effective
    • Air duct cleaning
    • Special vacuum cleaners
    • Air filters

Allergen - Cockroaches

  • Most Effective
    • Extermination with regular cleaning
  • Possibly Effective
    • Elimination of food and water sources
  • Least Effective
    • Extermination without regular cleaning

Allergen - Cats

  • Most Effective
    • Complete removal of cat
  • Possibly Effective
    • Move cat outdoors
  • Least Effective
    • Air filters
    • Carpet cleaners
    • Cat washing
Allergy Treatment At A Glance
  • Avoidance is always the best treatment for allergies.
  • There are many easy cleaning methods that can significantly decrease allergies.
  • Controlling the air quality and climate of your home can bring you tremendous health benefits.
  • If you are going to keep a pet that is a source of allergies, there are measures that you can take to optimize your home environment.



Diaper Rash

 

View Childhood Illnesses Slideshow Pictures

 

Childhood Illnesses Slideshow Pictures Childhood Illnesses Slideshow Pictures
Parenting and Healthy Eating Slideshow Pictures Parenting and Healthy Eating Slideshow Pictures
Parenting - Fitness and Exercise Slideshow Pictures Parenting - Fitness and Exercise Slideshow Pictures

Medical Author: John Mersch, MD, FAAP
Medical Editor: William C. Shiel Jr., MD, FACP, FACR

  • What is diaper rash?
  • Is diaper rash a sign of neglectful care?
  • What causes diaper rash?
  • What treatments are recommended for diaper rash?
  • How about not using disposable diapers?
  • How should an allergic rash be treated?
  • How about using cortisone cream?
  • How about using Neosporin?
  • Diaper Rash At A Glance
  • Find a local Pediatrician in your town

What is diaper rash?

Diaper rash is a generalized term indicating any skin irritation (regardless of cause) that develops in the diaper-covered region. Synonyms include diaper dermatitis (dermatitis = inflammation of the skin), napkin (or "nappy") dermatitis and ammonia dermatitis. While there are a several broad categories of causes of diaper rash, contact irritation is the most common culprit. While diaper rash is generally thought to affect infants and toddlers, any individual wearing a diaper (for example, an incontinent adult) is a candidate to develop this dermatitis.

Is diaper rash a sign of neglectful care?

No, not at all. Parents often incorrectly feel that the rash is a visual representation of poor caretaking skills. However, parents need to understand that the basic causes for this common kind of skin irritation are still under active debate in the field of dermatology and that neglectful parenting is not among the possible factors. In the United States, diaper dermatitis represents about 10%-20% of all skin disorders managed by a general pediatrician. While the rash may develop as early as the first week of life, the most frequent time period is between 9 and 12 months of age. Studies have indicated that, at any point in time, between 7%-35% of children in this age range are experiencing such a skin rash.

What causes diaper rash?

There are several categories of causes for this dermatitis. First and foremost is "irritant" or "contact" dermatitis. Skin involvement may vary from mild redness (similar in character to a sunburn) to erosion of the top layers of skin. A characteristic differential point of contract diaper dermatitis from other causes of diaper rash is that it rarely involves the skin fold regions -- therefore, it spares areas not in contact with urine/stool.

Skin infections compose the next most common category of diaper rash. Bacteria (Staph and Strep) and yeast/fungal (Candida) are common causes of diaper rash. Generally both of these types of infections tend to result from a disruption of skin integrity and overwhelming the natural defense mechanisms of skin in this diaper region. Staph and Strep bacterial infections are commonly termed impetigo. Classic descriptions of impetigo include small (1-2 mm) tiny blisters (vesicles) and pustules that tend to easily rupture leaving multiple erosions in a sea of generalized skin irritation. Candida diaper dermatitis also has several distinguishing patterns. The rash is characterized by zones of bright red skin with a series of discrete 2-4 mm "satellite" lesions at the borders of the confluent irritated skin. In contrast to contact dermatitis, Candida is generally only found in the skin folds creases and often around the anal region. Infectious causes of diaper dermatitis can generally be diagnosed by visual inspection alone. If confusion exists, laboratory studies of swabs of the involved areas may be obtained.

Allergic reactions are a less common cause of diaper rash. Commonly proposed allergens are fragrances and components of the diaper and wipes. These regions often have well-defined zones of redness with superficial vesicles and erosions. If the diagnosis of allergic skin reaction is suspect, skin-patch testing may be done to identify the offending agent. This is rarely necessary.

There are very rare causes of diaper rash. Unusual infections, metabolic and nutritional deficiency states, and immunodeficiency states and malignancies can all be implicated. Unfortunately, child abuse (hot-water immersion, extreme neglect to infant hygiene) can also present as diaper rash.

Less often, allergic reactions to the fragrances or other components found in disposable diapers or wipes can cause diaper rash.

What treatments are recommended for diaper rash?

The best treatment for diaper rash is avoidance of the precipitating agents which led to the contact irritation and to regions becoming secondarily infected by skin bacteria or yeast. Frequent diaper changes limit stool and urine exposure to the area and remain the foundation for prevention and management of diaper dermatitis.

Should a rash develop, simple cleansing with water and soft cloths tends to be less irritating to the injured skin than disposable wipes. Frequent application of one of the many diaper-area ointments containing either petroleum jelly (Vaseline) or zinc oxide (Desitin) provides an effective barrier against skin irritants and lessen friction to irritated skin. If the diaper rash is especially irritated by the rubbing necessary for proper hygiene, then using a non-sticky cream or ointment (such as Vaseline) as a barrier may be an important consideration. If sticky stool hinders hygiene, it may be more easily removed after application of mineral oil to the area. Most pediatricians find no benefit to using cornstarch or talcum power. The risk of possible aspiration of these powders underscores their general lack of significant efficacy. High-concentration baking soda or boric-acid baths are to be avoided due to possibility of toxicity associated with an increased rate of absorption due to skin breakdown.

Weather and/or carpet permitting, open-air exposure of the irritated skin is also extremely effective in helping clear up diaper rash. Many children have a therapeutic response to merely sitting in a warm-water bath twice daily for 15-20 minutes per session. The value of additional agents (including baking soda) is debatable.

Should these measures not provide a solid response within two to three days, the possibility of a secondary bacterial or yeast infection must be considered. The diaper region should be examined by a pediatrician unless the parent is confident in correctly making these diagnoses. Several topical antibiotic ointments are available for therapy in these situations.

How about not using disposable diapers?

Parents often wonder if switching from disposable to cloth diapers will lessen the likelihood of contact type diaper rash. In fact, the opposite seems to be true. The absorbent gel material found in most of today's disposable diapers draws moisture away from the skin area, thus helping to promote a healthy diaper area.

How should an allergic rash be treated?

For an allergic reaction to the fragrances or other components found in disposable diapers or wipes, eliminating the offending agents by using either simple water cleansing of the skin and a switch to another brand of disposable diapers or using cloth diapers instead is usually therapeutic.

How about using cortisone cream?

A minimally concentrated hydrocortisone cream may be recommended in certain cases. However, the excessive usage of minimally concentrated hydrocortisone cream and the use of increased potency hydrocortisone preparations are notorious for causing secondary side effects. They should only be used under the guidance of a pediatrician or another physician who is fully familiar with their application to infants.

How about using Neosporin?

This ointment (and others containing the topical antibiotic neomycin) should be avoided since neomycin is a very common allergen promoting an allergic skin reaction. Instead of helping the situation, such a medication may complicate and confuse the situation.

Diaper Rash At A Glance
  • Diaper rash is very common in babies and is not a sign of parental neglect.
  • Diaper rash is most commonly a kind of contact dermatitis.
  • Diaper rash may become secondarily infected by bacteria or yeast normally present on the skin. In this case, topical antibiotic ointments provide a rapid and effective therapy.
  • Avoidance of skin irritants by frequent diaper changing provides the number-one preventative measure.
  • Effective treatments include frequent diaper changes, application of topical barriers (for example, petroleum jelly), and rarely topical antibiotic/antifungal ointments, or low-potency hydrocortisone cream. High-potency steroid creams, powders, and concentrated baking-soda/boric-acid baths and neomycin-containing ointments are to be avoided.



Atopic Dermatitis

 

View Slideshow Pictures

 

10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
Nasal Allergy Relief Slideshow Pictures Nasal Allergy Relief Slideshow Pictures

Medical Author: Nili N. Alai, MD, FAAD
Medical Editor: William C. Shiel Jr., MD, FACP, FACR

  • What is atopic dermatitis?
  • What is the difference between atopic dermatitis and eczema?
  • How common is atopic dermatitis?
  • What causes atopic dermatitis?
  • Is atopic dermatitis contagious?
  • What are the symptoms of atopic dermatitis?
  • Can atopic dermatitis affect the face?
  • Is the sufferer's skin type important?
  • What are the stages of atopic dermatitis?
  • How is atopic dermatitis diagnosed?
  • What factors can aggravate atopic dermatitis?
  • What are skin irritants in patients with atopic dermatitis?
  • What are allergens?
  • What are aeroallergens?
  • What other factors may play a role in atopic dermatitis?
  • How is atopic dermatitis treated?
  • What is the hope for long-term management of atopic dermatitis?
  • Atopic Dermatitis At A Glance
  • Patient Discussions: Atopic Dermatitis - Treatments
  • Patient Discussions: Atopic Dermatitis - Describe Your Experience
  • Find a local Dermatologist in your town

 

What is atopic dermatitis?

Atopic dermatitis is a very common, often chronic (long-lasting) skin disease that affects a large percentage of the world's population. It is also called eczema, dermatitis, or atopy. Most commonly, it may be thought of as a type of skin allergy or sensitivity. The atopic dermatitis triad includes asthma, allergies (hay fever), and eczema. There is a known hereditary component of the disease, and it is seen more in some families. The hallmarks of the disease include skin rashes and itching.

The word "dermatitis" means inflammation of the skin. "Atopic" refers to diseases that are hereditary, tend to run in families, and often occur together. In atopic dermatitis, the skin becomes extremely itchy and inflamed, causing redness, swelling, cracking, weeping, crusting, and scaling. Dry skin is a very common complaint and an underlying cause of some of the typical rash symptoms.

Although atopic dermatitis can occur in any age, most often it affects infants and young children. In some instances, it may persist into adulthood or actually first show up later in life. A large number of patients tend to have a long-term course with various ups and downs. In most cases, there are periods of time when the disease is worse, called exacerbations or flares, which are followed by periods when the skin improves or clears up entirely, called remissions. Many children with atopic dermatitis enter into a permanent remission of the disease when they get older, although their skin may remain somewhat dry and easily irritated.

Multiple factors can trigger or worsen atopic dermatitis, including dry skin, seasonal allergies, exposure to harsh soaps and detergents, new skin products or creams, and cold weather. Environmental factors can activate symptoms of atopic dermatitis at any time in the lives of individuals who have inherited the atopic disease trait.

What is the difference between atopic dermatitis and eczema?

Eczema is used as a general term for many types of skin inflammation (dermatitis) and allergic-type skin rashes. There are different types of eczema, like allergic, contact, irritant, and nummular eczema. Several other forms have very similar symptoms. The diverse types of eczema are listed and briefly described below. Atopic dermatitis is typically a more specific set of three associated conditions occurring in the same person including eczema, allergies, and asthma. Not every component has to be present at the same time, but usually these patients are prone to all of these three related conditions.

Types of eczema

  • Contact eczema: a localized reaction that includes redness, itching, and burning where the skin has come into contact with an allergen (an allergy-causing substance) or with an irritant such as an irritating acid, a cleaning agent, or other chemical
  • Allergic contact eczema: a red, itchy, weepy reaction where the skin has come into contact with a substance that the immune system recognizes as foreign, such as poison ivy or certain preservatives in creams and lotions like Neosporin or Bacitracin
  • Seborrheic eczema (also called seborrheic dermatitis or seborrhea): is a very common form of mild skin inflammation of unknown cause that presents as yellowish, oily, scaly patches of skin on the scalp, face, ears, and occasionally other parts of the body. Often this is also called dandruff in adults or "cradle cap" in infants.
  • Nummular eczema: coin-shaped (round), isolated patches of irritated skin -- most commonly on the arms, back, buttocks, and lower legs -- that may be crusted, scaling, and extremely itchy
  • Neurodermatitis: a very particular type of dermatitis where the person frequently picks at their skin, causing rashes. The underling cause may be a sensitivity or irritation which sets off a cascade of repeated itching and scratching cycles. It may be seen as scratch marks and pick marks on the skin. Sometimes scaly patches of skin on the head, lower legs, wrists, or forearms caused by a localized itch (such as an insect bite) may become intensely irritated when scratched.
  • Stasis dermatitis: a skin irritation on the lower legs, generally related to circulatory problems and congestion of the leg veins. It may have a darker pigmentation, light-brown, or purplish-red discoloration from the congestion and back up of the blood in the leg veins. It's sometimes seen more in legs with varicose veins.
Stasis eczema on the leg
Picture of stasis eczema on the leg
  • Dyshidrotic eczema: irritation of the skin on the palms of hands (mostly) and less commonly soles of the feet characterized by clear, very deep-seated blisters that itch and burn. It's sometimes described as a "tapioca pudding"-like rash on the palms.

How common is atopic dermatitis?

Atopic dermatitis is very common worldwide and increasing in prevalence. It affects males and females equally and accounts for 10%-20 % of all referrals to dermatologists (doctors who specialize in the care and treatment of skin diseases). Atopic dermatitis occurs most often in infants and children, and its onset decreases substantially with age. Scientists estimate that 65% of patients develop symptoms in the first year of life, and 90% develop symptoms before the age of 5. Onset after age 30 is less common and often occurs after exposure of the skin to harsh conditions. People who live in urban areas and in climates with low humidity seem to be at an increased risk for developing atopic dermatitis.

About 10% of all infants and young children experience symptoms of the disease. Roughly 60% of these infants continue to have one or more symptoms of atopic dermatitis even after they reach adulthood. This means that more than 15 million people in the United States have symptoms of the disease.

What causes atopic dermatitis?

The cause of atopic dermatitis is not known, but the disease seems to result from a combination of genetic (hereditary) and environmental factors. There seems to be a basic hypersensitivity and an increased tendency toward itching. Evidence suggests that the disease is associated with other so-called atopic disorders such as hay fever (seasonal allergies) and asthma, which many people with atopic dermatitis also have. In addition, many children who outgrow the symptoms of atopic dermatitis go on to develop hay fever or asthma. Although one disorder does not necessarily cause another, they may be related, thereby giving researchers clues to understanding atopic dermatitis.

While emotional factors and stress may in some cases exacerbate or initiate the condition, they do not seem to be a primary or underlying cause for the disorder. In the past, there was some thought that perhaps atopic dermatitis was entirely caused by an emotional disorder.

Photo of atopic dermatitis on the ear
Photo of atopic dermatitis on the ear

Is atopic dermatitis contagious?

No. Atopic dermatitis itself is definitely not contagious and it cannot be passed from one person to another through skin contact. There is generally no cause for concern in being around someone with even an active case of atopic dermatitis, unless they have active skin infections.

Some patients with atopic dermatitis get secondary infections of their skin with Staphylococcus "staph," other bacteria, herpes virus (cold sores), and less commonly yeasts and other fungal infections. These infections may be contagious through skin contact.

What are the symptoms of atopic dermatitis?

Although symptoms may vary from person to person, the most common symptoms are dry, itchy, red skin. Itch is the grand hallmark of the disease. Typical affected skin areas include the folds of the arms, the back of the knees, wrists, face, and hands. Less commonly there may be cracks behind the ears, and various other rashes on any part of the body.

The itchy feeling is an important factor in atopic dermatitis, because scratching and rubbing in response to itching worsen the skin inflammation that is characteristic of this disease. People with atopic dermatitis seem to be more sensitive to itching and feel the need to scratch longer in response. They develop what is referred to as the "itch-scratch" cycle. The extreme itchiness of the skin causes the person to scratch, which in turn worsens the itch, and so on. Itching is particularly a problem during sleep, when conscious control of scratching decreases and the absence of other outside stimuli makes the itchiness more noticeable. Many patients also notice worsening of their itch in the early evening when they get home from work or school when there are less external stimuli to keep them occupied. When things at home sort of quiet down, the itching seems to become more noticeable.

How atopic dermatitis affects the skin can be changed by patterns of scratching and resulting skin infections. Some people with the disease develop red, scaling skin where the immune system in the skin becomes very activated. Others develop thick and leathery skin as a result of constant scratching and rubbing. This condition is called lichenification. Still others develop papules, or small raised bumps, on their skin. When the papules are scratched, they may open (excoriations) and become crusty and infected. The box below lists common skin features of the disease. These conditions can also be found in people without atopic dermatitis or with other types of skin disorders.

Photo of eczema on the hands
Photo of eczema on the hands

Can atopic dermatitis affect the face?

Yes. Atopic dermatitis may affect the skin around the eyes, the eyelids, the eyebrows, and lashes. Scratching and rubbing the eye area can cause the skin to change in appearance. Some people with atopic dermatitis develop an extra fold of skin under their eyes, called an atopic pleat or Dennie-Morgan fold. Other people may have hyperpigmented eyelids, meaning that the skin on their eyelids darkens from the inflammation or hay fever (allergic shiners). Patchy eyebrows and eyelashes may also result from scratching or rubbing.

The face is very commonly affected in babies who may drool excessively and become irritated from skin contact with their flowing saliva.

Is the sufferer's skin type important?

Yes. Differences in the skin of people with atopic dermatitis may contribute to the symptoms of the disease. The epidermis, which is the outermost layer of skin, is divided into two parts: the inner part, which contains moist, living cells, and the outer part, which consists of dry, flattened, dead cells. Under normal conditions, the outer layer of skin acts as a barrier, keeping the rest of the skin from drying out and protecting other layers of skin from damage caused by irritants and infections. When this barrier is damaged or is naturally thin, irritants act more intensely on the skin.

The skin of a person with atopic dermatitis loses too much moisture from the epidermal layer. This allows the skin to become very dry, which reduces its protective abilities. In addition, the skin is very susceptible to recurring disorders, such as staphylococcal and streptococcal bacterial skin infections, warts, herpes simplex, and molluscum contagiosum (which is caused by a virus).

Skin features of atopic dermatitis
  • Lichenification: thick, leathery skin resulting from constant scratching and rubbing
  • Lichen simplex: refers to a thickened patch of raised skin that results from repeat rubbing and scratching of the same skin area
  • Papules: small, raised bumps that may open when scratched, becoming crusty and infected
  • Ichthyosis: dry, rectangular scales on the skin, commonly on the lower legs and shins
  • Keratosis pilaris: small, rough bumps, generally on the face, upper arms, and thighs. These are also described as gooseflesh or chicken skin and may have a small coiled hair under each bump.
  • Hyper linear palms: increased number of skin creases on the palms
  • Urticaria: hives (red, raised bumps), often after exposure to an allergen, at the beginning of flares, or after exercise or a hot bath
  • Cheilitis: inflammation of the skin on and around the lips
  • Atopic pleat (Dennie-Morgan fold): an extra fold of skin that develops under the eye
  • Dark circles under the eyes: may result from allergies and atopy
  • Hyperpigmented eyelids: eyelids that have become darker in color from inflammation or hay fever
  • Prurigo nodules also called "picker's warts" are not really warts at all. These are small thickened bumps of skin caused by repeated picking of the same skin site.

 

Picture of eczema on the leg
Picture of eczema on the leg

What are the stages of atopic dermatitis?

Atopic dermatitis affects each child differently, both in terms of onset and severity of symptoms. In infants, atopic dermatitis typically begins around 6 to 12 weeks of age. It may first appear around the cheeks and chin as a patchy facial rash, which can progress to red, scaling, oozing skin. The skin may become infected. Once the infant becomes more mobile and begins crawling, exposed areas such as the knees and elbows may also be affected. An infant with atopic dermatitis may be restless and irritable because of the itching and discomfort. Many infants improve by 18 months of age, although they remain at greater than normal risk for dry skin or hand eczema later in life.

In childhood, the rash tends to occur behind the knees and inside the elbows, on the sides of the neck, and on the wrists, ankles, and hands. Often, the rash begins with papules that become hard and scaly when scratched. The skin around the lips may be inflamed, and constant licking of the area may lead to small, painful cracks. Severe cases of atopic dermatitis may affect growth, and the child may be shorter than average.

The disease may go into remission (disease-free period). The length of a remission varies, and it may last months or even years. In some children, the disease gets better for a long time only to come back at the onset of puberty when hormones, stress, and the use of irritating skin-care products or cosmetics may cause the condition to flare.

Although a number of people who developed atopic dermatitis as children also experience symptoms as adults, it is less common (but possible) for the disease to show up first in adulthood. The pattern in adults is similar to that seen in children; that is, the disease may be widespread or limited. In some adults, only the hands or feet may be affected and become dry, itchy, red, and cracked. Sleep patterns and work performance may be affected, and long-term use of medications to treat the condition may cause complications. Adults with atopic dermatitis also have a predisposition toward irritant contact dermatitis, especially if they are in occupations involving frequent hand wetting, hand washing, or exposure to chemicals. Some people develop a rash around their nipples. These localized symptoms are difficult to treat, and people often do not tell their doctor because of modesty or embarrassment. Adults may also develop cataracts that are difficult to detect because they cause no symptoms. Therefore, the doctor may recommend regular eye exams.

How is atopic dermatitis diagnosed?

Atopic dermatitis is generally easily diagnosed based on a physical exam and visual inspection of the skin by a physician or dermatologist. Additionally, the history given by the patient and contributory family history help to support the diagnosis. A physician may ask about any history of similar rashes and other medical problems including hay fever (allergies) and asthma. While currently there may be no single specific laboratory test that says unequivocally "this is atopic dermatitis," a skin biopsy (a sample of a small piece of skin that is sent to the lab for examination under the microscope) may be helpful to establish the diagnosis in harder cases. Additionally, gentle skin swabs (long cotton tip applicator or Q-tip) samples may be sent to the lab to exclude infections of the skin which may mimic atopic dermatitis.

Since itching tends to be the main common symptom of the disease for many patients, it is not possible to say all itching is atopic dermatitis. Itching may be seen in many other medical conditions that have nothing to do with eczema. Each patient experiences a unique combination of symptoms, and the symptoms and severity of the disease may vary over time. The doctor bases the diagnosis on the individual's symptoms and may need to see the patient several times to make an accurate diagnosis. It is important for the doctor to rule out other diseases and conditions that might cause skin irritation. In some cases, the family doctor or pediatrician may refer the patient to a dermatologist or allergist (allergy specialist) for further evaluation.

A valuable diagnostic tool is a thorough medical history, which provides important clues as to the possible causes of the patient's ailment. The doctor may ask about all of the following: a family history of allergic disease, whether the patient also has diseases such as hay fever or asthma, exposure to irritants, sleep disturbances, any foods that seem to be related to skin flares, previous treatments for skin-related symptoms, use of steroids, and the effects of symptoms on schoolwork, career, or social life. Sometimes, it is necessary to do a biopsy of the skin or patch testing to determine if the skin's immune system overreacts to certain chemicals or preservatives in skin creams. A preliminary diagnosis of atopic dermatitis can be made if the patient has three or more characteristics from each of two categories: major features and minor features. Some of these characteristics are listed in the box below.

Skin scratch/prick tests (which involve scratching or pricking the skin with a needle that contains a small amount of a suspected allergen) and blood tests for airborne allergens generally are not as useful in diagnosing atopic dermatitis as a medical history and careful observation of symptoms. However, they may occasionally help the doctor rule out or confirm a specific allergen that might be considered important in the diagnosis. Negative results on skin tests are reliable and may help rule out the possibility that certain substances are causing skin inflammation in the patient. However, positive skin scratch/prick test results are difficult to interpret in people with atopic dermatitis and are often inaccurate. In some cases, where the type of dermatitis is unclear, blood tests to check the level of eosinophils (a type of white blood cell) or IgE (an antibody whose levels are often high in atopic dermatitis) are helpful.

Major and minor features of atopic dermatitis

Major features

  • Itching
  • Characteristic rash in locations typical of the disease (arm folds and behind knees)
  • Chronic or repeatedly occurring symptoms
  • Personal or family history of atopic disorders (eczema, hay fever, asthma)

Some minor features
  • Early age of onset
  • Dry, rough skin
  • High levels of immunoglobulin E (IgE), an antibody, in the blood
  • Ichthyosis
  • Hyper linear palms
  • Keratosis pilaris
  • Hand or foot dermatitis
  • Cheilitis (dry or irritated lips)
  • Nipple eczema
  • Susceptibility to skin infection
  • Positive allergy skin tests

What factors can aggravate atopic dermatitis?

Many factors or conditions can intensify the symptoms of atopic dermatitis, including dry skin, winter or cold weather, wool cloths, and other irritating skin conditions. These factors may further trigger the itch-scratch cycle, further stimulating the many times already overactive immune system in the skin. Repeated aggravation and activation of the itch-scratch cycle may cause further skin damage and barrier breakdown. These exacerbating elements can be broken down into two main categories: irritants and allergens. Emotional factors and some infections can also influence atopic dermatitis.

What are skin irritants in patients with atopic dermatitis?

Irritants are substances that directly affect the skin, and when used in high enough concentrations with long enough contact cause the skin to become red and itchy or to burn. Specific irritants affect people with atopic dermatitis to different degrees. Over time, many patients and their families learn to identify the irritants that are most troublesome to them. For example, wool or synthetic fibers may affect some patients. Rough or poorly fitting clothing can rub the skin, trigger inflammation, and prompt the beginning of the itch-scratch cycle. Soaps and detergents may have a drying effect and worsen itching, and some perfumes and cosmetics may irritate the skin. Exposure to certain elements (such as chlorine, mineral oil, or solvents) or irritants (such as dust or sand) may also aggravate the condition. Cigarette smoke may irritate the eyelids. Because irritants vary from one person to another, each person has to determine for himself or herself what substances or circumstances cause the disease to flare.

Common irritants

  • Wool or synthetic fibers
  • Soaps and detergents
  • Some perfumes and cosmetics
  • Substances such as chlorine, mineral oil, or solvents
  • Dust or sand
  • Dust mites
  • Cigarette smoke
  • Animal fur or dander
  • Flowers and pollen

What are allergens?

Allergens are substances from foods, plants, or animals that provoke an overreaction of the immune system and cause inflammation (in this case, the skin). Inflammation can occur even when the person is exposed to small amounts of the allergen for a limited time. Some examples of allergens are pollen and dog or cat dander (tiny particles from the animal's skin or hair). When people with atopic dermatitis come into contact with an irritant or allergen to which they are sensitive, inflammation-producing cells permeate the skin from elsewhere in the body. These cells release chemicals that cause itching and redness. As the person scratches and rubs the skin in response, further damage occurs.

Certain foods act as allergens and may trigger atopic dermatitis or exacerbate it (cause it to become worse). Food allergens clearly play a role in a number of cases of atopic dermatitis, primarily in infants and children. An allergic reaction to food can cause skin inflammation (generally hives), gastrointestinal symptoms (vomiting, diarrhea), upper respiratory tract symptoms (congestion, sneezing), and wheezing. The most common allergy-causing (allergenic) foods are eggs, peanuts, milk, fish, soy products, and wheat. Although the data remain inconclusive, some studies suggest that mothers of children with a family history of atopic diseases should avoid eating commonly allergenic foods themselves during late pregnancy and while they are breastfeeding the baby. Although not all researchers agree, most experts think that breastfeeding the infant for at least four months may have a protective effect for the child.

If a food allergy is suspected, it may be helpful to keep a careful diary of everything the patient eats, noting any reactions. Identifying the food allergen may be difficult and require supervision by an allergist if the patient is also being exposed to other allergens. One helpful way to explore the possibility of a food allergy is to eliminate the suspected food and then, if improvement is noticed, reintroduce it into the diet under carefully controlled conditions. A two week trial is usually sufficient for each food. If the food being tested causes no symptoms after two weeks, a different food can be tested in like manner afterward. Likewise, if the elimination of a food does not result in improvement after two weeks, other foods may be eliminated in turn.

Changing the diet of a person who has atopic dermatitis may not always relieve symptoms. A change may be helpful, however, when a patient's medical history and specific symptoms strongly suggest a food allergy. It is up to the patient and his or her family and physician to judge whether the dietary restrictions outweigh the impact of the disease itself. Restricted diets often are emotionally and financially difficult for patients and their families to follow. Unless properly monitored, diets with many restrictions can also contribute to nutritional problems in children.

What are aeroallergens?

Some allergens are called aeroallergens because they are present in the air. They may also play a role in atopic dermatitis. Common aeroallergens are dust mites, pollens, molds, and dander from animal hair or skin. These aeroallergens, particularly the house dust mite, may worsen the symptoms of atopic dermatitis in some people. Although some researchers think that aeroallergens are an important contributing factor to atopic dermatitis, others believe that they are insignificant. Scientists also don't understand the way in which aeroallergens affect the skin -- whether the aeroallergen affects the person internally after being inhaled or whether the aeroallergen actually penetrates the patient's skin.

No reliable test is available that determines whether a specific aeroallergen is an exacerbating factor in any given individual. If the doctor suspects that an aeroallergen is contributing to a patient's symptoms, the doctor may recommend ways to reduce exposure to the offending agents. For example, the presence of the house dust mite can be limited by encasing mattresses and pillows in special dust-proof covers, frequently washing bedding in hot water, and removing carpeting. However, there is no way to completely rid the environment of aeroallergens.

What other factors may play a role in atopic dermatitis?

In addition to irritants and allergens, other factors, such as emotional issues, temperature and climate, and skin infections can affect atopic dermatitis. Although the disease itself is not caused by emotional factors or personality, it can be exacerbated by stress, anger, and frustration. Interpersonal problems or major life changes, such as divorce, job changes, or the death of a loved one, can also make the disease worse. Often, emotional stress seems to prompt a flare of the disease.

Bathing with harsh soaps like Ivory or Irish Spring and without proper moisturizing afterward is a common factor that triggers a flare of atopic dermatitis. Typical recommendations include using a very gentle soap-free cleanser or milder soap like Dove, Cetaphil, or Aquanil. The "three-minute rule" of lubricating with a rich moisturizer such as Vaseline, Aquaphor, or Crisco Vegetable Shortening within three minutes of drying off after a bath or shower is particularly helpful for many patients.

The low humidity of winter or the dry year-round climate of some geographic areas can intensify the disease, as can overheated indoor areas and long or hot baths and showers. Alternately, sweating and chilling can induce an attack in some people. Bacterial infections can also prompt or increase the severity of atopic dermatitis. If a patient experiences a sudden onset of illness, the doctor may check for a viral infection (such as herpes simplex) or fungal infection (such as ringworm or athlete's foot).

How is atopic dermatitis treated?

Treatment involves a partnership between the doctor and the patient and his or her family members. The doctor will suggest a treatment plan based on the patient's age, symptoms, and general health. The patient and family members play a large role in the success of the treatment plan by carefully following the doctor's instructions. Some of the primary components of treatment programs are described below. Most patients can be successfully managed with proper skin care and lifestyle changes and do not require the more intensive treatments discussed. Much of the improvement comes from homework, including lubricating generously especially right after showers or baths.

The doctor has three main goals in treating atopic dermatitis: healing the skin and keeping it healthy; preventing flares, and treating symptoms when they do occur. Much of caring for the skin involves developing skin-care routines, identifying exacerbating factors, and avoiding circumstances that stimulate the skin's immune system and the itch-scratch cycle. It is important for the patient and family members to note any changes in skin condition in response to treatment and to be persistent in identifying the most effective treatment strategy.

Skin care: A simple and basic regimen is key. Staying with one recommended soap and one moisturizer is very important. Using multiple soaps, lotions, fragrances, and mixes of products may cause further issues and skin sensitivity.

Healing the skin and keeping it healthy are of primary importance both in preventing further damage and enhancing the patient's quality of life. Developing and following a daily skin care routine is critical to preventing recurrent episodes of symptoms. Key factors are proper bathing and the application of lubricants, such as creams or ointments, within three minutes of bathing. People with atopic dermatitis should avoid hot or long (more than 10 to 15 minutes) baths and showers. A lukewarm bath helps to cleanse and moisturize the skin without drying it excessively. The doctor may recommend limited use of a mild bar soap or non-soap cleanser because soaps can be drying to the skin. Bath oils are not usually helpful.

Once the bath is finished, the patient should air-dry the skin or pat it dry gently (avoiding rubbing or brisk drying) and apply a lubricant immediately. Lubrication restores the skin's moisture, increases the rate of healing, and establishes a barrier against further drying and irritation. Several kinds of lubricants can be used. Lotions generally are not the best choice because they have a high water or alcohol content and evaporate quickly. Creams and ointments work better at healing the skin. Tar preparations can be very helpful in healing very dry, lichenified areas. Whatever preparation is chosen, it should be as free of fragrances and chemicals as possible.

Another key to protecting and restoring the skin is taking steps to avoid repeated skin infections. Although it may not be possible to avoid infections altogether, the effects of an infection may be minimized if they are identified and treated early. Patients and their families should learn to recognize the signs of skin infections, including tiny pustules (pus-filled bumps) on the arms and legs, appearance of oozing areas, or crusty yellow blisters. If symptoms of a skin infection develop, the doctor should be consulted to begin treatment as soon as possible.

Treating atopic dermatitis in infants and children

  • Give brief, lukewarm baths.
  • Apply lubricant immediately following the bath.
  • Keep a child's fingernails filed short.
  • Select soft cotton fabrics when choosing clothing.
  • Consider using antihistamines to reduce scratching at night.
  • Keep the child cool; avoid situations where overheating occurs.
  • Learn to recognize skin infections and seek treatment promptly.
  • Attempt to distract the child with activities to keep him or her from scratching.

Medications and phototherapy: If a recurrence of atopic dermatitis occurs, several methods can be used to treat the symptoms. With proper treatment, most symptoms can be brought under control within three weeks. If symptoms fail to respond, this may be due to a flare that is stronger than the medication can handle, a treatment program that is not fully effective for a particular individual, or the presence of trigger factors that were not addressed in the initial treatment program. These factors can include a reaction to a medication, infection, or emotional stress. Continued symptoms may also occur because the patient is not following the treatment-program instructions.

Corticosteroid creams and ointments are the most frequently used treatment. Sometimes, over-the-counter preparations are used, but in many cases, the doctor will prescribe a stronger corticosteroid cream or ointment. Occasionally, the base used in certain brands of corticosteroid creams and ointments is irritating for a particular patient and a different brand is required. Side effects of repeated or long-term use of topical corticosteroids can include thinning of the skin, infections, growth suppression (in children), and stretch marks on the skin.

Tacrolimus (Protopic) and pimecrolimus (Elidel) ointments are powerful topical medicated creams (drugs that are applied to the skin) that are used for the treatment of atopic dermatitis. These new drugs are referred to as "immune modulators." They were first and are still commonly used internally (oral form) to help patients with kidney and liver transplants avoid rejecting the organs they received. They work by suppressing the immune system. When these drugs are used in limited and small quantities on intact skin to externally to treat the skin, they are not thought to significantly weaken or change the body's immune system. Also, unlike topical steroids (cortisone creams), these new medications don't cause thinning of the skin and breaking of superficial blood vessels (atrophy). However, over the recent few years, there has been concern and a positional change by the Food and Drug Administration (FDA). A special warning has been placed on these two immune modulator drugs with potential caution regarding cancers and other immune-system suppression issues. While dermatologists and other physicians have continued to safely prescribe many of these drugs for children and adults, it is important to discuss these possible concerns and precautions with your physician when beginning a treatment regimen.

 

A newer class of drugs for improving barrier function in both pediatrics and adults includes Atopiclair and MimyX. These creams may be used in combination with topical steroids and other emollients to help repair the overall dryness and broken skin function.

Additional available treatments may help to reduce specific symptoms of the disease. Antibiotics to treat skin infections may be applied directly to the skin in an ointment but are usually more effective when taken by mouth in pill form. Certain antihistamines that cause drowsiness can reduce nighttime scratching and allow more restful sleep when taken at bedtime. This effect can be particularly helpful for patients whose nighttime scratching aggravates the disease. If viral or fungal infections are present, the doctor may also prescribe medications to treat those infections.

Phototherapy is treatment with light that uses ultraviolet A or B light waves or a combination of both. This treatment can be an effective treatment for mild to moderate dermatitis in older children (over 12 years old) and adults. Photochemotherapy, a combination of ultraviolet light therapy and a drug called psoralen, can also be used in cases that are resistant to phototherapy alone. Possible long-term side effects of this treatment include premature skin aging and skin cancer. If the doctor thinks that phototherapy may be useful in treating the symptoms of atopic dermatitis, he or she will use the minimum exposure necessary and monitor the skin carefully.

When other treatments are not effective, the doctor may prescribe systemic corticosteroids, drugs that are taken by mouth or injected into muscle instead of being applied directly to the skin. An example of a commonly prescribed corticosteroid is prednisone. Typically, these medications are used only in resistant cases and are only given for short periods of time. The side effects of systemic corticosteroids can include skin damage, thinned or weakened bones, high blood pressure, high blood sugar, infections, and cataracts. It can be dangerous to suddenly stop taking corticosteroids, so it is very important that the doctor and patient work together in changing the corticosteroid dose.

Previous clinical trials using drugs like self-injectable interferon treatments demonstrated mixed results and have not become mainstream treatments. The most common side effects with interferon involve mild injection-site reactions and possible fever or flu-like symptoms. These drugs maybe used in severe or challenging situations that don't respond to more traditional treatments.

In adults, immunosuppressive drugs, such as cyclosporine, are also used to treat severe cases of atopic dermatitis that have failed to respond to any other forms of therapy. Immunosuppressive drugs restrain the overactive immune system by blocking the production of some immune cells and curbing the action of others. The side effects of cyclosporine can include high blood pressure, nausea, vomiting, kidney problems, headaches, tingling or numbness, and a possible increased risk of cancer and infections. There is also a risk of relapse after the drug is discontinued. Because of their toxic side effects, systemic corticosteroids and immunosuppressive drugs are used only in severe cases and then for as short a period of time as possible. Patients requiring systemic corticosteroids or immunosuppressive drugs should be referred to a dermatologist or an allergist specializing in the care of atopic dermatitis to help identify trigger factors and alternative therapies.

In extremely rare cases, when no other treatments have been successful, the patient may have to be hospitalized. A five- to seven-day hospital stay allows intensive skin-care treatment and reduces the patient's exposure to irritants, allergens, and the stresses of day-to-day life. Under these conditions, the symptoms usually clear quickly if environmental factors play a role or if the patient is not able to carry out an adequate skin-care program at home.

Tips for working with your doctor

  • Provide complete, accurate medical information about yourself or your child.
  • Make a list of your questions and concerns in advance.
  • Be honest and share your point of view with the doctor.
  • Ask for clarification or further explanation if you need it.
  • Talk to other members of the health-care team, such as nurses, therapists, or pharmacists.
  • Don't hesitate to discuss sensitive subjects with your doctor.
  • Discuss changes to any medical treatment or medications with your doctor before making them.

Atopic dermatitis and quality of life

Despite the symptoms caused by atopic dermatitis, it is possible for people with the disorder to maintain a high quality of life. The keys to an improved quality of life are education, awareness, and developing a partnership among the patient, family, and doctor. Good communication is essential for all involved. It is important that the doctor provides understandable information about the disease and its symptoms to the patient and family and demonstrate any treatment measures recommended to ensure that they will be properly carried out.

When a child has atopic dermatitis, the entire family situation may be affected. It is important that families have additional support to help them cope with the stress and frustration associated with the disease. The child may be fussy and difficult and often is unable to keep from scratching and rubbing the skin. Distracting the child and providing as many activities that keep the hands busy is key but requires much effort and work on the part of the parents or caregivers. Another issue families face is the social and emotional stress associated with disfigurement caused by atopic dermatitis. The child may face difficulty in school or other social relationships and may need additional support and encouragement from family members.

Adults with atopic dermatitis can enhance their quality of life by caring regularly for their skin and being mindful of other effects of the disease and how to treat them. Adults should develop a skin-care regimen as part of their daily routine, which can be adapted as circumstances and skin conditions change. Stress management and relaxation techniques may help decrease the likelihood of flares due to emotional stress. Developing a network of support that includes family, friends, health professionals, and support groups or organizations can be beneficial. Chronic anxiety and depression may be relieved by short-term psychological therapy.

Recognizing the situations when scratching is most likely to occur may also help. For example, many patients find that they scratch more when they are idle. Structured activity that keeps their hands occupied may prevent further damage to the skin. Occupational counseling also may be helpful to identify or change career goals if a job involves contact with irritants or involves frequent hand washing, such as kitchen work or auto mechanics.

Controlling atopic dermatitis

  • Lubricate the skin frequently.
  • Avoid harsh soaps and cleansers.
  • Prevent scratching or rubbing whenever possible.
  • Protect skin from excessive moisture, irritants, and rough clothing.
  • Maintain a cool, stable temperature and consistent humidity levels.
  • Limit exposure to dust, cigarette smoke, pollens, and animal dander.
  • Recognize and limit emotional stress.

What is the hope for long-term management of atopic dermatitis?

Although symptoms of atopic dermatitis can be very difficult and uncomfortable, the disease can be successfully managed. People with atopic dermatitis, as well as their families, can lead healthy, normal lives. Long-term management may include treatment with an allergist to control internal allergies and a dermatologist to monitor the skin-care component.

Atopic Dermatitis At A Glance
  • Atopic dermatitis is a type of eczema.
  • The skin sensitivity of this disease may be inherited and genetically determined.
  • The patient's skin may be "super sensitive" to many irritants.
  • Dry scaly patches develop in a characteristic distribution.
  • Itching varies but may be intense and scratching hard to resist.
  • Scratching can cause skin thickening and darkening and lead to further complications, including bacterial infection.
  • Extremely dry skin can break down and ooze or weep.
  • If the itch can be controlled, the rash (which is aggravated by vigorous scratching) may be more readily contained.
  • Treatment of atopic dermatitis is centered around rehydrating the skin with rich moisturizers like Vaseline and cautious use of topical steroids to reduce inflammation and itching.
  • Oral antihistamines are often necessary to break the "itch-scratch" cycle.
  • Since secondary infections can aggravate the rash, topical or oral antibiotics may also be occasionally indicated.


Eye Allergy
(Allergic Eye Disease)

 

View the Eye Diseases and Conditions Slideshow Pictures

 

 

 

 

Eye Diseases and Conditions Slideshow Pictures Eye Diseases and Conditions Slideshow Pictures
Pink Eye Slideshow Pictures Pink Eye Slideshow Pictures
Cataracts Slideshow Pictures Cataracts Slideshow Pictures

Medical Author: Jay Robert Woody, MD
Medical Editor: Melissa Conrad Stöppler, MD

  • Eye allergy introduction
  • What is the basic anatomy of the outer eye?
  • Why are the eyes an easy target for allergies?
  • What are allergic eye conditions?
  • What are eyelid allergies (also called contact eye allergies)?
  • What conditions can be confused with eye allergies?
  • How do we care for allergic eyes?
  • Eye Allergy At A Glance
  • Patient Discussions: Eye Allergy
  • Find a local Asthma & Allergy Specialist in your town

Eye allergy introduction

Picture of eye allergies

The eyes are the windows to the soul because they reflect our state of mind. This certainly can't be true if our eyes are red, swollen, watery, and itchy from an allergic reaction. Severe allergic eye symptoms can be very distressing and are a common reason for visits to the allergist, ophthalmologist, and even the emergency room. Occasionally, severe eye allergies cause serious damage that can threaten eyesight.

Eye allergies usually are associated with other allergic conditions, particularly hay fever (allergic rhinitis) and atopic eczema (dermatitis). The causes of eye allergies are similar to those of allergic asthma and hay fever. Medications and cosmetics can play a significant role in causing eye allergies. Reactions to eye irritants and other eye conditions (for example, infections such as pinkeye) are often confused with eye allergy.

What is the basic anatomy of the outer eye?

Eye allergies mainly involve the conjunctiva, which is the tissue lining (mucus membrane) that covers the white surface of the eyeball and the inner folds of the eyelids. The conjunctiva is a barrier structure that is exposed to the environment and the many different allergens (substances that stimulate an allergic response) that become airborne. It is rich in blood vessels and contains more mast cells (histamine-releasing cells) than the lungs.

The lacrimal (tear) glands are located in the upper and outer portions of the eye. They are responsible for producing the watery component of tears, which keeps the eye moist and washes away irritants. The tears also contain important components of the immune defense such as immunoglobulin (antibodies), lymphocytes (specialized white blood cells), and enzymes.

The cornea is the transparent sheath in front of the lens of the eye. The cornea has no blood vessels and very little immune activity.

Why are the eyes an easy target for allergies?

When you open your eyes, the conjunctiva becomes directly exposed to the environment without the help of a filtering system such as the cilia, the hairs commonly found in the nose.

Allergy fact

Approximately 54 million people, about 20% of the U.S. population, have allergies. Almost half of these people have allergic eye disease.

People who are more susceptible to allergic eye disease are those with a history of allergic rhinitis and atopic dermatitis and those with a strong family and/or personal history of allergy. Symptoms usually appear before the age of 30.

The scenario for developing allergy symptoms is much the same for the eyes as that for the nose. Allergens cause the allergy antibody IgE to coat numerous mast cells in the conjunctiva. Upon reexposure to the allergen, the mast cell is prompted to release histamine and other mediators. The result is itching, burning, and runny eyes that become red and irritated due to inflammation, which results in congestion. The eyelids may swell, even to the point of closing altogether. Sometimes, the conjunctiva swells with fluid and protrudes from the surface of the eye, resembling a "hive" on the eye. These reactions may also induce light sensitivity. Typically, both eyes are affected by an allergic reaction. Occasionally, only one eye is involved, particularly when only one eye is rubbed with an allergen, as this causes mast cells to release more histamine.

Allergic conjunctivitis is inflammation of the conjunctiva that is caused by a reaction to allergens. The inflammation causes enlargement of the blood vessels in the conjunctiva ("congestion"), resulting in a red or bloodshot appearance of the eyes.

What are allergic eye conditions?

Allergic conjunctivitis

Allergic conjunctivitis, also called "allergic rhinoconjunctivitis," is the most common allergic eye disorder. The condition is usually seasonal and is associated with hay fever. The main cause is pollens, although indoor allergens such as dust mites, molds, and dander from household pets such as cats and dogs may affect the eyes year-round. Typical complaints include itching, redness, tearing, burning, watery discharge, and eyelid swelling. To a large degree, the acute (initial) symptoms appear related to histamine release.

The treatments of choice are topical antihistamine drops such as olopatadine (Patanol), decongestants, and the newer mast-cell stabilizer medications. Topical steroids should be used only if prescribed by a doctor for severe reactions and on a short-term basis because of the potential for side effects. In general, oral antihistamines like loratadine (Claritin) or cetirizine (Zyrtec) are the least effective option, but they are often used for treating allergic rhinitis together with allergic conjunctivitis.

 

Allergy assist

Rubbing itchy eyes is a natural response. However, rubbing usually worsens the allergic reaction due to the physical impact on the mast cells, which causes them to release more mediators of the immune response. Translation: Do not rub your eyes!

Conjunctivitis with atopic dermatitis

Commonly called "atopic keratoconjunctivitis," this condition is a notorious cause of severe eye changes, particularly in young adults. Atopic keratoconjunctivitis implies inflammation of both the conjunctiva and cornea. "Kerato" means pertaining to the cornea. This form of conjunctivitis usually affects adolescent boys (three times more frequently than girls) and is more common in those who had atopic dermatitis in early childhood. The condition is characterized by intensely itchy, red areas that appear on the eyelids. A heavy discharge from the eyes can occur, and the skin of the eyelid may show scales and crusts. In severe cases, the eyes become sensitive to light, and the eyelids noticeably thicken. If managed poorly, there can be permanent scarring of the cornea due to chronic rubbing and scratching of the eyes. This scarring can cause visual changes.

The triggers for atopic keratoconjunctivitis appear to be similar to those of atopic dermatitis. A search for common food allergies, such as eggs, peanuts, milk, soy, wheat, or fish is important. Airborne allergens, particularly dust mites and pet dander, have been overlooked as a significant contributing factor and should be evaluated and controlled.

The hallmark of treatment for allergic conjunctivitis is the use of potent antihistamines (similar to those used in atopic dermatitis) to subdue the itching. Topical antihistamines, mast-cell stabilizers, and the short-term use of oral steroids are all beneficial for relief of the itching. Occasionally, an infection of the area (usually with staphylococcus, commonly referred to as "staph") worsens the symptoms, and antibiotic treatment may help control the itching. Allergy shots are useful in selected cases.

Allergy alert

Atopic keratoconjunctivitis can lead to cataract formation in up to 10% of cases. In rare cases, blindness can occur.

Vernal keratoconjunctivitis

Vernal keratoconjunctivitis is an uncommon condition that tends to occur in preadolescent boys (3:1 male to female ratio) and is usually outgrown during the late teens or early adulthood. (Vernal is another term for "spring.") Vernal keratoconjunctivitis usually appears in the late spring and particularly occurs in rural areas where dry, dusty, windy, and warm conditions prevail. The eyes become intensely itchy, sensitive to light, and the lids feel uncomfortable and droopy. The eyes produce a "stringy" discharge and, when examined, the surface under the upper eyelids appears "cobblestoned." A closer examination of the eye reveals severe inflammation due to the vast number of mast cells and accumulated eosinophils, producing so-called called "Trantas dots."

Improper treatment of vernal keratoconjunctivitis can lead to permanent visual impairment. The most effective treatment appears to be a short-term course of low-dose topical steroids. Topical mast-cell stabilizers and topical antihistamines can also be beneficial. Wraparound sunglasses are helpful to protect the eyes against wind and dust.

Allergy fact

Keratitis, or the inflammation of the cornea, in vernal and atopic keratoconjunctivitis is largely caused by a substance that is released from the eosinophils, called major basic protein.

Giant papillary conjunctivitis (GPC)

This condition is named for its typical feature, large papillae, or bumps, on the conjunctiva under the upper eyelid. These bumps are likely the result of irritation from a foreign substance, such as contact lenses. Hard, soft, and rigid gas-permeable lenses are all associated with the condition. The reaction is possibly linked to the protein buildup on the contact lens surface. This condition is believed, in part, to be due to an allergic reaction to either the contact lens itself, protein deposits on the contact lens, or the preservative in the solution for the contact lenses. Redness and itching of the eye develop, along with a thick discharge.

Allergy to contact lenses is most common among wearers of hard contact lenses and is least common among those who use disposable lenses, especially the one-day or one-week types. Sleeping with the contact lenses on greatly increases the risk of developing GPC.

The most effective treatment is to stop wearing the contact lenses. Occasionally, changing the type of lens in addition to more frequent cleaning or using disposable daily wear lenses will prevent the condition from recurring.

The giant papillae on the conjunctiva, which are characteristic of GPC, however, may persist for months despite these measures. Eye medications, such as cromolyn (Opticrom) or lodoxamide (Alomide), often are used in this condition, sometimes for several months. Contact lenses should not be worn while these medications are being used

What are eyelid allergies (also called contact eye allergies)?

Contact eye allergies are essentially contact dermatitis of the eyelids. This is allergic inflammation of the eyelid from direct contact with certain allergens. Women in particular may experience this problem due to allergic reactions to preservatives in eye products and makeup (for example, eye creams, eye pencils, mascara, and nail polish -- from rubbing the eye with the fingers). Other irritants include common over-the-counter (OTC) ointments such as neomycin/bacitracin/polymyxin (Neosporin or Bacitracin) as well as contact lens solutions (especially if they contain thimerosal). Symptoms that are similar to those of a poison ivy rash appear 24 to 48 hours after exposure to the offending agent. The eyelids may develop blisters, itching, and redness. The conjunctiva may also become red and watery. If the eyelids continually come into contact with the offending allergens, the lids may become chronically (long-term) inflamed and thickened.

The best treatment for eyelid allergies is avoidance of the sensitizing agent(s). Changing to hypoallergenic lens solutions, cosmetics, or topical eye products is usually necessary. Application of a mild topical corticosteroid cream for short periods will probably help. As is the case with atopic dermatitis, it is important to treat any secondary bacterial infection that may develop.

What conditions can be confused with eye allergies?

The following is a list of conditions, the symptoms of which are commonly confused with eye allergy.

  • Dry eye: This condition results from reduced tear production and is frequently confused with allergy. The main symptoms are usually burning, grittiness, or the sensation of "something in the eye." Dry eye usually occurs in people over 65 years of age and can certainly be worsened by oral antihistamines like diphenhydramine (Benadryl), hydroxyzine (Atarax), Claritin, or Zyrtec, sedatives, and beta-blocker medications.
  • Tear-duct obstruction: This is caused by a blockage in the tear passage that extends from the eyes to the nasal cavity. This condition is also typically seen in the elderly. The main complaint is watery eyes that do not itch. Allergy testing will be negative in this case.
  • Conjunctivitis due to infection can be caused by either bacteria or viruses. In bacterial infections, the eyes are often "bright red" and the eyelids stick together, especially in the morning. A discolored mucous discharge is often seen, so-called "dirty eyes." Viral conjunctivitis causes slight redness of the eyes and a glassy appearance from tearing. Adenovirus is a major cause of viral conjunctivitis. The herpes virus, such as that which causes chickenpox or shingles, can also affect the eye. Adenovirus infection is very contagious and may be spread by either direct contact, such as hand contact, or in contaminated swimming pools. You should seek medical attention if you suspect any of the above.
 

 

Allergy assist
  • If your eye itches and is "milky" red, it is most likely allergy.
  • If it burns, it is probably dry eye.
  • If it "sticks" in the morning and is bright red, it is usually bacterial or viral conjunctivitis.

How do we care for allergic eyes?

Most people with eye allergies treat themselves and do so quite effectively with OTC products. If these remedies are not working or if there is eye pain, extreme redness, or heavy discharge, you should seek medical advice. Some conditions, for example, are serious with potential sight-threatening complications if required treatment is delayed.

Allergy assist

Moistening the eyes with artificial tears helps to dilute accumulated allergens and also prevents the allergens from sticking to the conjunctiva. Tear substitutes may also improve the defense function of the natural tear film.

Avoid the triggers

Avoidance is once again the cornerstone of allergy treatment. It is particularly important to avoid both airborne and contact allergens. Remember, rubbing your eyes is a physical trigger and therefore must be avoided.

Topical antihistamines & decongestants

Antihistamine eyedrops work by blocking histamine receptors in the conjunctiva. The histamine, therefore, is unable to attach to the conjunctiva and exert its effects. They are effective in relieving itching but have little impact on swelling or redness. They have two advantages over antihistamine tablets; there is a quicker onset of action and less drying of the eye. The new generation of topical antihistamines includes emedastine difumarate (Emadine) and levocabastine (Livostin). The side effects of these medications include mild stinging and burning of the eyes upon use, headaches, and sleepiness. But treatment with antihistamines at the point of irritation is still preferable than treating systemically with oral antihistamines if possible.

Decongestants take the redness away as advertised. However, they do not help relieve itching. They act by shrinking the blood vessels on the conjunctiva. (They are not really effective against allergic eyes.) The decongestants, oxymetazdine (Visine LR) and tetrahydrozoline hydrochloride (Visine Original) are available OTC. They do have a potential for abuse and should not be used by people with narrow-angle glaucoma, an eye disease characterized by elevated pressure within the eye.

Allergy assist

The prolonged use of decongestant nasal sprays can produce a rebound phenomenon in which the medication begins to cause more congestion than it relieves. This phenomenon rarely occurs in the eyes with the repeated use of decongestant drops. The mucous membranes of the eye are different from those of the nose. The eyes can become irritated and less responsive to the drops, but unlike the nose, the eyes tend not to develop "rebound" redness.

Combination antihistamine-decongestant preparations can provide quick relief that lasts a few hours. They lessen the itch, redness, and swelling and are very useful for milder symptoms. Common combinations include pheniramine with naphcyoline hydrochloride (Naphcon-A or Opcon-A) and antazoline with naphazoline (Vasocon-A). Side effects are minimal, but the drops may become less effective if used for prolonged periods. They do have a potential for abuse and should not be used by people with narrow-angle glaucoma.

Topical mast-cell stabilizers

Mast-cell stabilizers prevent the release of chemical mediators of inflammation from the mast cells. These are effective for all eye allergies. The first of this class of drug was cromolyn sodium (Crolom or Opticrom), which is available OTC. This topical medicine has been effective for treating mild cases of vernal keratoconjunctivitis and probably mild allergic rhinoconjunctivitis and has no significant side effects. It does have a slow onset of action. The newer agent, lodoxamide (Alomide), is 2,500 times more potent than Crolom and has a faster onset of action. This prescription medicine may be used in children older than 2 years of age and has minimal side effects. One disadvantage is the need to use the drops four times a day, and long-term use is necessary to prevent symptoms.

The most effective mast-cell stabilizer, which also has antihistamine properties, is Patanol. Available by prescription, it is 250 times more effective than Alomide in relieving itching and redness. This drug provides rapid relief of itching and burning eyes. It can also prevent symptoms when used before an exposure or before the pollen season. The drops are very comfortable in the eye and can by used in children as young as 3 years old. The longer duration of action allows dosing of twice a day.

Another new product, ketotifen (Zaditor), also has dual mast-cell-stabilizing and antihistamine effects. It dramatically reduces itching and redness and gives more rapid relief within minutes.

 

Topical antiinflammatory drugs

Nonsteroidal antiinflammatory drugs (NSAIDS) are particularly useful in treating itchy eyes. They reduce redness and swelling to a lesser degree. Ketorolac (Acular) is a topical NSAID, which may cause temporary stinging and burning in 40% of users.

 

Steroid antiinflammatory eyedrops are very effective in treating eye allergies, but they are reserved for severe symptoms that are unresponsive to other treatments. They must be used with caution in people with bleeding tendencies because they can increase the bleeding risk. Since there are significant risks with long-term treatment, their use should be supervised by an ophthalmologist.

Caution must be taken, however, because of the potential side effects of the long-term use of steroids, even in eye drop form. Side effects of steroids include elevated pressure in the eyes and cataracts. The elevated pressure in the eyes can become glaucoma and lead to damage of the optic (eye) nerve and loss of vision. Cataracts are a clouding or opacification of the clear natural lens within the eye, which can interfere with vision. The purpose of the lens is to focus the light or images that enter the eye. Remember, however, that the side effects of steroids usually occur with long-term use and that steroid eyedrops may be very effective when used over the short term. Loteprednol etabonate (Alrex) is a new short-acting steroid with fewer side effects that shows great promise in the treatment of allergic eye disease.

 

Allergy alert

Topical steroids may cause or worsen glaucoma and result in cataracts with long-term use. About 500 drops of a high-dose preparation can cause cataracts. Also, remember that with topical steroid eyedrops, short-term, low-potency preparations are recommended and should only be used under the supervision of an ophthalmologist.

Systemic medications

Oral antihistamines, either OTC or prescription (non- or lightly sedating), may be used for itchy eyes. The OTC products may cause drowsiness, and both can cause drying of the eyes.

 

Allergy assist

In general, treating topical conditions with topical medications is preferable. Why involve the whole body when locally effective alternatives are available?

Allergy shots (immunotherapy)

When avoidance of offending allergens and local treatments are not effective, allergy shots may be indicated. Your allergist may suggest this form of treatment when other measures have been unsuccessful.

Here are a few general tips worth remembering:

  • Eyes that are dry may aggravate eye allergy symptoms. Tear substitutes, such as artificial tears, are an often forgotten but are an effective lubricant and a wonderful treatment.
  • Cold compresses may help, particularly with sudden allergic reactions and swollen eyes.
  • Keep eyedrops refrigerated since this makes application more soothing.

 

Eye Allergy At A Glance
  • Most allergic eye conditions are more irritating than dangerous.
  • Allergic or vernal keratoconjunctivitis may result in scarring of the cornea and visual problems.
  • Itchy eyes are probably allergic eyes.
  • Topical antihistamine/decongestant preparations are effective and safe for mildly itchy, red eyes.
  • Patanol, a topical mast-cell stabilizer, is a safe, highly effective, long-acting treatment.
  • Topical steroids should be used with caution and under the supervision of an ophthalmologist.
  • If in doubt, seek medical advice sooner rather than later.


Food Allergy

 

Food Allergy Triggers & Where They Hide Pictures Slideshow

 

Food Allergy Triggers & Where They Hide Slideshow Pictures Food Allergy Triggers & Where They Hide Slideshow Pictures
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers Slideshow Pictures

Medical Author: Melissa Conrad Stöppler, MD
Medical Editor: William C. Shiel Jr., MD, FACP, FACR

  • Food allergy facts
  • Introduction to food allergies
  • How do allergic reactions to food occur?
  • What are the symptoms and signs of food allergy?
  • Do infants and children have problems with food allergy?
  • What are the most common food allergies?
  • What is cross-reactivity?
  • What is oral allergy syndrome?
  • What is exercise-induced food allergy?
  • What conditions have mistakenly been attributed to food allergy?
  • What conditions mimic food allergy?
  • How is food allergy diagnosed?
  • What is the treatment for a food allergy?
  • Are allergy shots effective for food allergy?
  • Pictures of Food Allergy Triggers & Where They Hide - Slideshow View Food Allergy Triggers & Where They Hide Slideshow
  • Take the Quiz on AllergiesTake the Quiz on Allergies
  • Pictures of 10 Common Allergy Triggers - Slideshow View 10 Common Allergy Triggers Slideshow
  • Patient Discussions: Food Allergy - Symptoms
  • Patient Discussions: Food Allergy - Describe Your Experience
  • Find a local Asthma & Allergy Specialist in your town

Food allergy facts

  • Food allergy is not common but can be serious.
  • Food allergy differs from food intolerance, which is far more common.
  • The more frequent types of food allergies in adults differ from those in children.
  • Children can outgrow their food allergies, but adults usually do not.
  • The diagnosis of food allergy is made with a detailed history, the patient's diet diary, or an elimination diet.
  • Food allergy is treated primarily by dietary avoidance.

Introduction to food allergies

Either food allergy or food intolerance affects nearly everyone at some point. When people have an unpleasant reaction to something they ate, they often think that they have an allergy to the food. Actually, however, only about 3% of adults and 6%-8% of children have clinically proven true allergic reactions to food.

This difference between the prevalence of clinically proven food allergy and the public's perception of the problem is due primarily to misinterpreting food intolerance or other adverse reactions to food as food allergy. A true food allergy is an abnormal response to food that is triggered by a specific reaction in the immune system and expressed by certain, often characteristic, symptoms. Other kinds of reactions to foods that are not food allergies include food intolerances (such as lactose or milk intolerance), food poisoning, and toxic reactions. Food intolerance also is an abnormal response to food, and its symptoms can resemble those of food allergy. Food intolerance, however, is far more prevalent, occurs in a variety of diseases, and is triggered by several different mechanisms that are distinct from the immunological reaction responsible for food allergy.

People who have food allergies must identify and prevent them because, although usually mild and not severe, these reactions can cause devastating illness and, in rare instances, can be fatal.

How do allergic reactions to food occur?

The allergens in food are those components that are responsible for inciting an allergic reaction. They are proteins that usually resist the heat of cooking, the acid in the stomach, and the intestinal digestive enzymes. As a result, the allergens survive to cross the gastrointestinal lining, enter the bloodstream, and go to target organs, causing allergic reactions throughout the body. The mechanism of food allergy involves the immune system and heredity.

Immune system: An allergic reaction to food involves two components of the immune system. One component is a type of protein, an allergy antibody called immunoglobulin E (IgE), which circulates through the blood. The other is the mast cell, a specialized cell that stores up histamine and is found in all tissues of the body. The mast cell is particularly found in areas of the body that are typically involved in allergic reactions, including the nose and throat, lungs, skin, and gastrointestinal tract.

Heredity: The tendency of an individual to produce IgE against something seemingly as innocuous as food appears to be inherited. Generally, people with allergies come from families in which allergies are common -- not necessarily to food but perhaps allergies to pollen, fur, feathers, or drugs. Thus, a person with two allergic parents is more likely to develop food allergies than someone with one allergic parent.

Mechanism: Food allergy is a hypersensitivity reaction, meaning that before an allergic reaction to an allergen in food can occur, a person needs to have been exposed previously, or "sensitized," to the food. At the initial exposure, the allergen stimulates lymphocytes (specialized white blood cells) to produce the IgE antibody that is specific for the allergen. This IgE then is released and attaches to the surface of the mast cells in different tissues of the body. The next time the person eats that particular food, its allergen hones in on the specific IgE antibody on the surface of the mast cells and prompts the cells to release chemicals such as histamine. Depending upon the tissue in which they are released, these chemicals cause the various symptoms of food allergy.

What are the symptoms and signs of food allergy?

The complex process of digestion affects the timing, location, and particular symptoms of an allergic reaction to food. All of the symptoms of food allergy occur within a few minutes to an hour of eating. A food allergy can initially be experienced as an itching in the mouth and difficulty swallowing and breathing. Then, during digestion of the food in the stomach and intestines, symptoms such as nausea, vomiting, diarrhea, and abdominal pain can start. Incidentally, the gastrointestinal symptoms of food allergy are those that are most often confused with the symptoms of different types of food intolerance.

As mentioned previously, the allergens are absorbed and enter the bloodstream. When they reach the skin, allergens can induce hives or eczema, and when they reach the airways, they can cause asthma. As the allergens travel through the blood vessels, they can cause lightheadedness, weakness, and anaphylaxis, which is a sudden drop in blood pressure. Anaphylactic reactions are severe even when they start off with mild symptoms, such as a tingling in the mouth and throat or discomfort in the abdomen. They can be fatal if not treated quickly.

Do infants and children have problems with food allergy?

Most allergies to foods begin in the first or second year of life. While some of these reactions may resolve over time (such as allergies to cow's milk or eggs), other food allergies acquired in infancy (such as allergies to nuts or shellfish) typically persist throughout life. Allergies to milk or soy formula (a milk substitute made from soybeans) sometimes occur in infants and young children. These early allergies sometimes do not involve the usual hives or asthma but rather can cause symptoms in babies resembling infantile colic, and perhaps blood in the stool, or poor growth.

The clinical picture of infantile colic, which usually starts within one month of birth, is that of a crying child who sleeps poorly at night. The cause of colic is uncertain. A variety of psychosocial and dietary factors have been implicated, however, and allergy to milk or soy has been proposed as a cause of colic in a minority of infants with colic.

In infants, food allergy is usually diagnosed by observing the effect of changing the infant's diet; rarely, by using a food challenge. If the baby is on cow's milk, the doctor will suggest a change to soy formula or breast milk only, if possible. If the soy causes an allergic reaction, the baby can be placed on an elemental formula. These formulas are processed proteins and carbohydrates, basically amino acids and sugars, and contain few, if any, allergens.

Breastfeeding: Exclusive breastfeeding, that is, excluding all other foods, for at least the first four months of life appears to help protect high-risk children against milk allergy and eczema in the first two years of life. Breast milk contains less protein that is foreign to the infant and, therefore, is less allergenic than cow's milk or soy formula. Exclusive breastfeeding should be a consideration, therefore, especially in infants who are predisposed to food allergy. Some children are so sensitive to a certain food, however, that if the mother eats that food, sufficient quantities enter the breast milk to cause a reaction to the food in the child. In this situation, the mothers themselves must avoid eating those foods to which the baby is allergic. No conclusive evidence has been obtained that suggests that breastfeeding prevents the development of allergies later in life.

Special considerations in children: An allergic child who itches, sneezes, and wheezes a lot can feel miserable and, therefore, sometimes misbehave or appear hyperactive. At the other extreme, children who are on allergy medicines that can cause drowsiness may become sleepy in school or at home. Parents and caregivers must understand these different behaviors, protect the children from the foods that induce their allergies and know how to manage an allergic reaction, including how to administer epinephrine. Also, schools need to have plans in place to address emergencies, including anaphylactic shock.

What are the most common food allergies?

In adults, the most common foods that cause allergic reactions are shellfish, such as shrimp, crayfish, lobster, and crab; nuts from trees, such as walnuts; fish; eggs; and peanuts, a legume that is one of the chief foods that cause serious anaphylactic reactions. In highly allergic people, even minuscule amounts of a food allergen (for example, 1/44,000 of a peanut kernel) can evoke an allergic reaction. Less sensitive people, however, may be able to tolerate small amounts of a food to which they are allergic.

In children, the pattern is somewhat different from adults, and the most common foods that cause allergic reactions are eggs, milk, peanuts, and fruits, particularly tomatoes and strawberries. Children sometimes outgrow their allergies, but adults usually do not lose theirs. Also, children are more likely to outgrow allergies to cow's milk or soy formula than allergies to peanuts, fish, or shrimp. Adults and children tend to react to those foods they eat more often. For example, in Japan, allergy to rice, and in Scandinavia, allergy to codfish, is more common than elsewhere.

What is cross-reactivity?

Cross-reactivity is the occurrence of allergic reactions to foods that are chemically or otherwise related to foods known to cause allergy in an individual. If someone has a life-threatening reaction to a certain food, the doctor will counsel that patient to avoid related foods, which also might induce the same reaction. For example, if a person has a history of a severe allergy to shrimp, he or she can also possibly be allergic to crab, lobster, and crayfish.

What is oral allergy syndrome?

The oral allergy syndrome is another type of cross-reactivity. This syndrome occurs in people who are highly sensitive, for example, to ragweed or birch pollen. During the seasons that these allergens pollinate, the affected individual may find that when he or she tries to eat fruits, chiefly melons and apples, a rapid onset of itching is experienced in the mouth and throat, and the fruit cannot be eaten. The oral allergy syndrome is also known as or pollen-food allergy syndrome and is thought to be a type of contact allergy related to the presence of proteins in certain foods that cross react with allergy-causing pollen proteins. Oral allergy syndrome occurs in up to 50% of those who have allergic rhinitis caused by pollen. Symptoms are immediate upon ingestion of fresh or uncooked foods and include the itching, irritation, and mild swelling of the lips, tongue, palate, and throat. Cooked fruits and vegetables usually do not cause the reaction. The symptoms usually go away within minutes, although up to 10% of people will develop systemic (body-wide) symptoms, and a small number (1%-2%) may experience anaphylactic shock. Tree nuts and peanuts tend to cause more severe reactions than other foods.

What is exercise-induced food allergy?

Exercise can induce an allergic reaction to food. The usual scenario is that of a person eating a specific food and then exercising. As he exercises and his body temperature increases, he begins to itch, gets lightheaded, and soon develops the characteristic allergic reactions of hives, asthma, abdominal symptoms, and even anaphylaxis. This condition has been referred to as food-dependent exercise-induced anaphylaxis (FDEIA) and is most common in teens and young adults. The cure, actually a preventive measure, for exercise-induced food allergy is simple -- not eating for at least two hours before exercising.

What conditions have mistakenly been attributed to food allergy?

Studies have shown that individuals who are prone to migraines can have their headaches brought on by histamine, which is one of the compounds that mast cells produce in an allergic reaction. The theory that food allergies can cause migraine headaches, however, is unproven. There is also inadequate scientific evidence to support the claims that food allergies can cause or aggravate rheumatoid arthritis, osteoarthritis, tension-fatigue syndrome, cerebral allergy (headaches and difficulty concentrating), environmental-toxic reactions, or hyperactivity in children.

What conditions mimic food allergy?

There are many conditions that can mimic food allergy. It is critical to distinguish true food allergy from other abnormal responses to food, that is, from food intolerance, which can occur in a variety of other illnesses or food poisoning, which occurs when contaminated food is ingested. If a patient says to the doctor, "I think I have a food allergy," the doctor has to consider a number of diagnoses. The possibilities include not only food allergy but also any other diseases that have symptoms brought on by food. These include reactions to certain chemicals in food for example, histamine or food additives, food poisoning, several other gastrointestinal diseases, and psychological symptoms.

Histamine toxicity: Some natural substances (for example, histamine) in foods can cause reactions resembling allergy. Histamine can reach high levels in cheese, some wines, and certain fish, particularly tuna and mackerel. In fish, the histamine is believed to stem from bacterial contamination, especially in fish that has not been refrigerated properly. Remember that mast cells release histamine in an allergic reaction. If a person eats a food that contains a high level of histamine, therefore, he may develop histamine toxicity, a response that strongly resembles an allergic reaction to food. Histamine toxicity has been referred to as pseudoallergic fish poisoning and accounts for over one-third of seafood-related food-borne illnesses, according to the U.S. Centers for Disease Control and Prevention (CDC).

Food additives: Another type of food intolerance is an adverse reaction to certain compounds that are added to food to enhance taste, provide color, or protect against the growth of microorganisms. Consumption of large amounts of these additives can produce symptoms that mimic the entire range of allergic symptoms. (Although some doctors attribute hyperactivity in children to food additives, the evidence is not compelling, and the cause of this behavioral disorder remains uncertain.)

The compounds most frequently tied to adverse reactions that can be confused with food allergy are yellow dye number 5, monosodium glutamate (MSG), and sulfites. Yellow dye number 5 can cause hives, although rarely. MSG enhances flavor, but when consumed in large amounts, can cause flushing, sensations of warmth, lightheadedness, headache, facial pressure, pain in the chest, and feelings of detachment. These symptoms occur soon after eating large amounts of food containing added MSG and are temporary.

Sulfites occur naturally in some foods and wines and are added to others to enhance crispness or prevent the growth of mold. In high concentrations, sulfites can pose problems for people with severe asthma. The sulfites emit a gas called sulfur dioxide, which the asthmatic inhales while eating the food containing sulfites. This gas irritates the lungs and can induce in an asthmatic a severe constriction of the air passages to the lungs (bronchospasm), making breathing very difficult. Such reactions led the U.S. Food and Drug Administration (FDA) to ban the use of sulfites as spray-on preservatives for fresh fruits and vegetables. Sulfites, however, are still added to some foods, and they also form during the fermentation of wine.

Food poisoning: Eating food that is contaminated with microorganisms, such as bacteria, and their products, such as toxins, is the usual cause of food poisoning. Thus, the ingestion of contaminated eggs, salad, milk, or meat can produce symptoms that mimic food allergy. Common microbes that can cause food poisoning include the noroviruses, Campylobacter jejuni, Salmonella, Listeria monocytogenes, Vibrio vulnificus, and E. coli 0157:H7.

Lactase deficiency (lactose intolerance): Another cause of food intolerance, which often is confused with a food allergy, specifically to milk, is lactase deficiency. This common food intolerance affects at least one out of 10 people. Lactase is an enzyme in the lining of the small intestine. This enzyme digests or breaks down lactose, a complex sugar in milk, to simple sugars, which are then absorbed into the blood. If a person has lactase deficiency, he does not have enough lactase to digest the lactose in most milk products. Instead, other bacteria in the intestine use the undigested lactose, thereby producing gas. Symptoms of lactose intolerance include bloating, abdominal pain, and diarrhea. In a diagnostic test for lactase deficiency, the patient ingests a specific amount of lactose. Then, by analyzing a blood sample for simple sugars, the doctor determines the patient's ability to digest the lactose and absorb the simple sugars. A lower than normal value usually means a lactase deficiency.

Gluten-sensitive enteropathy: Intolerance to gluten occurs in a disease called gluten-sensitive enteropathy, or celiac sprue. Gluten-sensitive enteropathy is caused by a unique abnormal immune response to certain components of gluten, which is a constituent of the cereal grains wheat, rye, and barley. Although sometimes referred to as an allergy to gluten, this immune response involves a branch of the immune system that is different from the one involved in a classical food allergy. The patients have an abnormality in the lining of the small intestine and experience diarrhea and malabsorption, especially of dietary fat. The treatment for this condition involves the avoidance of dietary gluten.

Other gastrointestinal diseases: Several other gastrointestinal diseases produce abdominal symptoms (especially nausea, vomiting, diarrhea, and pain) that are sometimes caused by food. These diseases, therefore, can resemble food allergies. Examples include peptic ulcer, gallstones, non-ulcer dyspepsia (which is a type of indigestion), Crohn's disease (regional enteritis), cancers of the gastrointestinal tract, and a rare condition called eosinophilic gastroenteritis.

Psychological: Some people have a food intolerance that has a psychological origin. In these people, a careful psychiatric evaluation may identify a traumatic event in that person's life, often during childhood, tied to eating a particular food. The eating of that food years later, even as an adult, is associated with a rush of symptoms that can resemble an allergic reaction to food.

How is food allergy diagnosed?

To diagnose food allergy, a doctor first must determine if the patient is having an adverse reaction to specific foods. The doctor makes this assessment with the help of a detailed history from the patient, the patient's dietary diary, or an elimination diet. He or she then confirms the diagnosis by the more objective skin tests, blood tests, or food challenges.

History: The history usually is the most important diagnostic tool in diagnosing food allergy. The physician interviews the patient to determine if the facts are consistent with a food allergy. The doctor may ask the following questions:

  • What was the timing of the reaction? Did the reaction come on quickly, usually within an hour after eating the food?
  • Was treatment for allergy successful? For example, if hives stem from a food allergy, antihistamines should relieve them.
  • Is the reaction always associated with a certain food?
  • Did anyone else get sick? For example, if the person has eaten fish contaminated with histamine, everyone who ate the fish should be sick. In an allergic reaction, however, only the person allergic to the fish becomes ill.
  • How much did the patient eat before experiencing a reaction? The severity of the patient's reaction can sometimes relate to the amount of the suspect food eaten.
  • How was the food prepared? Some people will have a violent allergic reaction only to raw or undercooked fish. A thorough cooking of the fish destroys those allergens in the fish to which they react, so that they then can eat it with no allergic reaction.
  • Were other foods eaten at the same time as the food that caused the allergic reaction? Fatty foods can delay digestion and thus delay the onset of the allergic reaction.

Dietary diary: Sometimes, a history alone cannot determine the diagnosis. In that situation, the doctor may ask the patient to keep a record of the contents of each meal and whether reactions occurred that are consistent with allergy. The dietary diary provides more details than the oral history, so that the doctor and patient can better determine if there is a consistent relationship between a food and the allergic reactions.

Elimination diet: The next step that some doctors use is an elimination diet. Under the doctor's direction, the patient does not eat a food suspected of causing the allergy, for example, eggs, and substitutes another food, in this instance, another source of protein. If after the patient removes the food, the symptoms go away, the doctor almost always can make a diagnosis of food allergy. If the patient then resumes eating the food (still under the doctor's direction) and the symptoms return, this sequence confirms the diagnosis. The patient should not resume eating the food, however, if the allergic reactions have been severe because this re-challenge is too risky. This technique is also not suitable if the allergic reactions have been infrequent.

If the patient's history, dietary diary, or elimination diet suggests that a specific food allergy is likely, the doctor then will use tests, such as skin tests, blood tests, and a food challenge, which can more objectively confirm an allergic response to food.

Skin tests: In a scratch-the-skin test, a dilute extract of the suspected food is placed on the skin of the forearm or back. This portion of the skin then is scratched with a needle and observed for swelling or redness, which would signify a local allergic reaction to the food. A positive scratch test indicates that the patient has the IgE antibody that is specific for the food being tested on the skin's mast cells. Skin tests are rapid, simple, and relatively safe.

A person can have a positive skin test to a food allergen, however, without experiencing allergic reactions to that food. A doctor diagnoses a food allergy only when the patient has a positive skin test to a specific allergen and the history suggests an allergic reaction to the same food. In some highly allergic people, however, especially if they have had anaphylactic reactions, skin tests should not be done because they could provoke another dangerous reaction. Skin tests also cannot be done in patients with extensive eczema.

Blood tests: In those situations where skin tests cannot be done, a doctor may use blood tests such as the RAST and the ELISA. These tests measure the presence of food-specific IgE antibodies in the blood of patients, but they cost more than skin tests, and the results are not available immediately. As with positive skin tests, positive blood tests make the diagnosis of a specific food allergy only when the clinical history is compatible.

Food challenge: The double-blind food challenge has become the gold standard for objective allergy testing. (Some physicians prefer the term double-masked, rather than double-blind.) In this test, various foods, some of which are suspected of inducing an allergic reaction, are placed in individual opaque capsules. Both the patient and the doctor are blinded, so that neither of them knows which capsules contain the suspected allergens. (The capsules are prepared by another medical worker.) The patient swallows a capsule and the doctor then observes whether an allergic reaction occurs. This process is repeated with each capsule. Alternatively, the food to be tested may be disguised in another type of food to which the person is not allergic.

The advantage of a food challenge is that if the patient has an allergic reaction only to the suspected foods and not to the other foods tested, the diagnosis of food allergy is confirmed. Just as with a re-challenge after the elimination diet and with the skin tests, however, someone having a history of severe reactions should not be tested with a food challenge because of the danger of inducing another severe reaction. In addition, this procedure is expensive because it is difficult and requires a lot of time, especially for patients with multiple food allergies. This type of test must also be done under the careful supervision of a physician. Consequently, double-blind food challenges are done infrequently. They are done most commonly, however, when the doctor wishes to obtain evidence to confirm the suspicion that the patient's symptoms are not due to a food allergy. Then, additional efforts may be directed at finding the real cause of the patient's symptoms.

What is the treatment for a food allergy?

Dietary avoidance: Avoiding the offending allergen in the diet is the primary treatment of food allergy. Once a food to which the patient is sensitive has been identified, the food must be removed from the diet. To do this, affected people need to read lengthy, detailed lists of ingredients on the label for each food they consider eating. Many allergy-producing foods such as peanuts, eggs, and milk appear in foods that are not ordinarily associated with them. For example, peanuts often are used as protein supplements, eggs are found in some salad dressings, and milk is in bakery products. The FDA requires that the ingredients in a food be listed on its label. People can avoid most of the foods to which they are sensitive if they carefully read the labels on foods and, when in restaurants, avoid ordering foods that might contain ingredients to which they are allergic.

Treating an anaphylactic reaction: People with severe food allergies must be prepared to treat an anaphylactic reaction. Even those who know a lot about their own allergies can either make an error or be served food that does not comply with their instructions. To protect themselves, people who have had anaphylactic reactions to a food should wear medical alert bracelets or necklaces stating that they have a food allergy and that they are subject to severe reactions. These individuals also always should carry a syringe of adrenaline (epinephrine [EpiPen]), obtained by prescription from their doctors, and be prepared to self-administer it if they think they are developing an allergic reaction. They then should immediately seek medical help by either calling the rescue squad or having themselves transported to an emergency room.

 

Treating other symptoms of food allergy: Several medications are available for treating the other symptoms of food allergy. For example, antihistamines can relieve gastrointestinal symptoms, hives, sneezing, and a runny nose. Bronchodilators can relieve the symptoms of asthma. These medications are taken after a person inadvertently has ingested a food to which he is allergic. They are not effective, however, in preventing an allergic reaction when taken prior to eating the food. In fact, no medication in any form is available to reliably prevent an allergic reaction to a certain food before eating that food.

Are allergy shots effective in preventing or decreasing food allergy?

Allergy shots, a form of treatment known as immunotherapy, involve injecting small quantities of substances to which the patient is allergic. The shots are given regularly for a long time with the aim of desensitizing the patient or getting the patient to tolerate the allergen without developing symptoms. This type of therapy is effective in controlling symptoms of allergies related to hay fever, indoor allergens, and insect stings. Researchers, however, have not yet proven that these shots can prevent any allergic reactions to food.

Summary

Food allergy is caused by immune reactions to foods, sometimes in individuals or families predisposed to allergies. A number of foods, especially shellfish, milk, eggs, peanuts, and fruit can cause allergic reactions (notably hives, asthma, abdominal symptoms, lightheadedness, and anaphylaxis) in adults or children. When a food allergy is suspected, a medical evaluation is the key to proper management.

It is important to distinguish a true food allergy from other abnormal responses to food, that is, food intolerances, which actually are far more common than food allergy. Once the diagnosis of food allergy is made (primarily by the medical history) and the allergen is identified (usually by skin tests), the treatment basically is to avoid the offending food. People with food allergies should work with their physicians and become knowledgeable about allergies and how they are diagnosed and treated.


Stinging Insect Allergies
(Bee Stings, Wasp Stings, Others)

 

View Slideshow Pictures

 

10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
Nasal Allergy Relief Slideshow Pictures Nasal Allergy Relief Slideshow Pictures

Medical Author: Melissa Conrad Stöppler, MD
Medical Editor: William C. Shiel Jr., MD, FACP, FACR

  • What are stinging insects?
  • Who is at risk for insect sting allergies?
  • What types of insect sting reactions occur?
  • How is a severe allergic reaction immediately treated?
  • How can I avoid insect stings?
  • What can I do about becoming immune to insect allergy?
  • Stinging Insect Allergies At A Glance
  • Find a local Asthma & Allergy Specialist in your town

What are stinging insects?

Stinging insects found in the United States include honeybees, yellow jackets, hornets, wasps, and fire ants. While not everyone is allergic to insect venom, reactions in the skin such as mild pain, swelling, and redness may occur with an insect sting.

Who is at risk for insect sting allergies?

Over 2 million Americans are allergic to stinging insects. The degree of allergy varies widely. Most people are not allergic to insect stings, and most insect stings result in only local itching and swelling. Many, however, will have severe allergic reactions. Severe allergic reactions to insect stings are responsible for at least 50 deaths each year in the U.S.

If you are known to be allergic to insect stings, then the next sting is 60% likely to be similar or worse than the previous sting. Since most stings occur in the summer and fall, you are at greatest risk during these months. Males under the age of 20 are the most common victims of serious insect-sting allergic reactions, but this may reflect a greater exposure to insects of males, rather than a true predisposition.

What types of insect sting reactions occur?

Nonallergic reactions

Most insect-sting reactions are not allergic and result in local pain, itching, swelling, and redness at the site of the sting. Some extension of the swelling is expected. Local treatment is usually all that is needed for this type of reaction. Disinfect the area, keep it clean, and apply ice. Topical corticosteroid creams are sometimes used to decrease inflammation, and antihistamines can help control itching.

Large local reactions may involve increased swelling (that lasts for 48 hours up to one week) that may be accompanied by nausea and vomiting. Large local reactions occur in about 10% of insect stings and are not allergic in origin. Occasionally, the site of an insect sting will become infected, and antibiotics are needed.

Allergic reactions

Systemic (body-wide) reactions are allergic responses and occur in people who have developed antibodies against the insect venom from a prior exposure. It is estimated that between 0.3%-3% of stings trigger a systemic allergic reaction.

The allergic reaction to an insect sting varies from person to person. Symptoms of an allergic reaction can include itching, hives, flushing of the skin, tingling or itching inside the mouth, and nausea or vomiting. The most serious allergic reaction is called anaphylaxis, which can be fatal. Difficulty breathing, swallowing, hoarseness, swelling of the tongue, dizziness, and fainting are signs of a severe allergic reaction. These types of reactions usually occur within minutes of the sting but have been known to be delayed for up to 24 hours. Prompt treatment is essential, and emergency help is often needed.

How is a severe allergic reaction immediately treated?

Honeybee stingers are barbed stingers that are left behind in the person's skin after the initial sting. If the stinger is removed by pinching the stinger, more venom is actually injected into the skin. It is better to remove the stinger by gently lifting the stinger using a fingernail or knife edge to flick the stinger out of the skin. Other stinging insects do not leave stingers behind and this technique does not apply.

An allergic reaction is treated with epinephrine (adrenaline). Several self-injectable devices are available by prescription, including Epi-Pen, ANA-Kit, and others. These devices are filled with the epinephrine to be injected in to the subcutaneous tissue or muscle, preferably into the front of the thigh. These self-injected devices usually contain only one dose and, on occasion, more than one dose is needed. Venom extractors are commercially available, but they have not been demonstrated to have any benefit.

If a serious sting reaction occurs, always seek medical attention, even if epinephrine is used and all seems stable. The allergic reaction can subsequently progress and become more serious after epinephrine has worn off. Sometimes epinephrine is not enough and intravenous fluids or other treatment is needed. If you are known to be seriously allergic to insects, you must remember to carry the epinephrine at all times especially when out of reach of medical care (such as in the woods or even on an airplane). If epinephrine is not available when you are stung, contact a doctor as soon as possible. In addition to epinephrine, an oral dose of antihistamine (like Benadryl) can reduce the symptoms of an allergic reaction. Antihistamines take effect in about one hour. Ultimately, however, it is crucial to attempt to avoid the sting.

How can I avoid insect stings?

Obviously, the best treatment is avoiding the insect sting. Certain precautionary measures will greatly decrease your chances of being stung. Honeybees are not aggressive and will usually not sting unless disturbed or injured. The majority of honeybee stings are on the bottom of the bare foot while stepping on the bee. Avoid walking barefoot on lawns where honeybees or other stinging insects may be present. Yellow jackets nest in the ground and in walls. Caution should be used with unusual forms in walls and mounds in the ground. Hornets and wasps often nest in bushes, in trees, and under roofs. Use caution too in these areas and in selecting employment requiring exposure to these conditions.

Bright colors attract insects seeking nectar. Stinging insects are attracted to food and strong smells. Avoid open food in garbage cans, dumps, and open picnic areas. Do not wear perfumes, hair sprays, and colognes. Keep the body covered as much as possible with light-colored clothing. Insect repellents are not effective against stinging insects.

What can I do about becoming immune to insect allergy?

All people who have had a significant reaction to a stinging insect should be evaluated by an allergy specialist for possible venom immunotherapy (allergy shots that develop an immunity to insect allergy). Selected patients with significant sensitivity to insect venom and specific symptoms can undergo allergy injection therapy for stinging-insect allergy. Allergy immunotherapy against stinging insects in these selected patients is almost 100% effective.

This type of treatment usually involves a gradually increasing dose of the venom over 10-20 weeks. Then a "maintenance" dosage every four to eight weeks is given. After approximately three to five years, discontinuation of the venom shot is considered. Therapy for three to five years confers long-term protection in most people. The risk of severe adverse reactions from this venom therapy is minimal (less than 0.2%), and no deaths have been reported to date.

The U.S. Department of Agriculture recommends the following:

  • Avoid disturbing likely beehive sites, such as large trees, tree stumps, logs, and large rocks.
  • If a colony is disturbed, run and find cover as soon as possible. Running in a zigzag pattern may be helpful.
  • Never stand still or crawl into a hole or other space with no way out.
  • Do not slap at the bees.
  • Cover as much of the head and face as possible, without obscuring vision, while running.
  • Once clear of the bees, remove stingers and seek medical care if necessary, especially if there is a history of allergy to bee venom.
Stinging Insect Allergies At A Glance
  • Severity of reactions to stings varies greatly.
  • Most insect stings do not produce allergic reactions.
  • Anaphylactic reactions are the most serious reactions and can be fatal.
  • Avoidance and prompt treatment are essential.
  • Epinephrine (available in portable, self-injectable form) is the treatment of choice for anaphylactic reactions.
  • In selected people, allergy injection therapy is highly effective in preventing future reactions.
  • The three "A's" of insect allergy are adrenaline, avoidance, and allergist.


Latex Allergy

 

View Slideshow Pictures

 

10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
Nasal Allergy Relief Slideshow Pictures Nasal Allergy Relief Slideshow Pictures
  • Why latex?
  • What is latex and where is it found?
  • Who is at risk?
  • How is latex allergy detected?
  • How is latex allergy treated?
  • Latex-Containing Products
  • Latex Allergy At A Glance
  • Find a local Asthma & Allergy Specialist in your town

Why latex?

In 1987, there was a movement throughout the world to take precautions that would prevent the spread of infectious diseases, especially the AIDS virus. This effort resulted in the application of universal precautions for protecting a person from infectious material using protective barriers. One such barrier was the latex glove. It is estimated that since 1987, the annual United States usage of latex gloves has been 10 billion. This increase in the use of latex has resulted in a dramatic rise in allergy to latex. Health care workers are at particular risk for latex allergy and it is estimated that this allergy affects 2% of all hospital employees. Latex is used in over 40,000 products.

What is latex and where is it found?

Latex is a natural product which comes from the light milky fluid that is extracted from the rubber tree. This milky fluid is often modified during the manufacturing process to form a latex mixture. A person can be allergic to the latex or the mixture or both. Latex-containing products are many and varied (see the list below). One of two procedures is employed during the manufacturing of the latex-containing product. One procedure is "dipping," wherein a form is dipped into a vat of latex and after drying, the latex product is washed and then peeled from the form. If the latex product is not washed well, as is the case with rushed production, more "free" latex is present on the surface. This "free" latex is responsible for a great deal of latex allergy. Dipped latex products include gloves, balloons and condoms. A much less allergic latex product is made by molding the latex. Products such as rubber stoppers and erasers are manufactured using this process. The powder of surgical gloves is a significant problem. Latex will easily stick to powder that is commonly used in surgical gloves.

When the glove is placed on or taken off the hand the glove is frequently "snapped." This snapping places the powder, with latex sticking to it, into the air. Inhaled latex can be a serious allergic problem.

Who is at risk?

Some people are born with a genetic predisposition to be allergic to latex. However, repeated exposure to latex is necessary for an allergy to develop. If a person is repeatedly exposed to latex, especially products that are "dipped," the risk of latex allergy substantially increases. Therefore, persons at risk are health care workers exposed to latex products (such as gloves and catheters), people who require frequent surgery or catheter use, and workers in the manufacturing or distribution of latex products. For unknown reasons, people who have surgeries of the spine or urinary tract have a much higher risk of latex allergy for reasons unknown.

There is also an interesting association of unique food allergy among persons allergic to latex. People allergic to latex are frequently allergic to bananas and sometimes other foods like kiwi, papaya, avocados and apricots. This association with food allergy is real, but the cause of the relationship is uncertain.

How is latex allergy detected?

Allergy to latex comes in two different forms. One form is called a "delayed hypersensitivity" which is usually seen as a skin rash at the site where the latex product contacts the skin. This rash can be quite severe. A more dangerous form of latex allergy is an "immediate reaction" to latex. This is also referred to as anaphylaxis. Anaphylaxis can result in seriously low blood pressure, breathing difficulty, and even death. Some patients can experience irritation of the nasal passages similar to hay fever (allergic rhinitis).

To detect the delayed hypersensitivity reaction, latex, its preservatives and accelerators are placed on the skin using a standard patch test. Caution is used because an immediate reaction is possible with patch testing. To detect an immediate reaction, a blood test and skin test is available. With latex allergy, the blood test is performed first because of the potential severe reaction.

How is latex allergy treated?

Avoidance of the provoking agent (allergen), such as latex, is the most effective way to manage any allergy. Latex free synthetic rubber, such as neoprene, nitrile, SBR, Butyl, and Vitron are polymers that are available as alternatives to natural rubber. There are no naturally occurring proteins in them and they are NOT responsible for latex allergy. Labeling is extremely important, but mandatory labeling is currently not required.

 

Patients who are known to be allergic should avoid any product that might contain latex until the latex content is determined by contacting the manufacturer. Even products labeled "safe latex" (which indicates lower proportions of natural latex) can cause latex allergy. There is no safe latex for latex allergic sufferers. Federal legislation is pending on truth and labeling for latex products. Powderless gloves are a great help in preventing airborne latex and have been very helpful in reducing surgical exposure of latex for the health care worker and the patient. No current treatment is available to desensitize the person allergic to latex. Treatment of reactions includes antihistamines, adrenaline, and steroids.

Latex-Containing Products (partial list):

Band-Aids, rubber bands, erasers, some shoes and articles of clothing, balloons, surgical gloves, catheters, condoms, some items of sporting equipment , blood pressure cuffs, some watch bands, helmets, tooth brush massagers, bowling balls and ventilator tubing.

Latex Allergy At A Glance
  • Latex allergy is dramatically on the rise throughout the world.
  • Latex allergy rises with exposure and is suspected to continue to rise until a latex substitute is found.
  • Latex allergy can be serious.
  • Latex is found in more than 40,000 products and is a common component of surgical gloves.


Poison Ivy, Oak, and Sumac

 

View Slideshow Pictures

 

10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
Nasal Allergy Relief Slideshow Pictures Nasal Allergy Relief Slideshow Pictures

Medical Authors: Alan Rockoff, MD, and Melissa Conrad Stöppler, MD
Medical Editor: William C. Shiel Jr., MD, FACP, FACR

  • Poison ivy, oak, and sumac facts
  • What causes the rash? How do I identify poison ivy, oak, and sumac?
  • What are the signs and symptoms of the poison ivy rash?
  • How is the dermatitis of poison ivy, oak, and sumac diagnosed?
  • What is the treatment for poison ivy, oak, and sumac dermatitis?
  • How can contact with poison ivy, oak, and sumac be prevented?
  • Find a local Dermatologist in your town

Poison ivy, oak, and sumac facts

  • Many people are susceptible to the rashes of poison ivy, oak, and sumac.
  • The sap oil, called urushiol, causes the skin rash.
  • Poison ivy is not contagious.
  • Washing the oily sap from the skin with water and soap immediately can help prevent the rash.
  • Avoiding direct contact with the plants can prevent the rash.

What causes the rash? How do I identify poison ivy, oak, and sumac?

Poison ivy is a common cause of contact dermatitis, an allergic reaction to something that comes in direct contact with the skin. Allergic contact dermatitis as a response to plants is sometimes referred to as allergic phytodermatitis. This condition can be quite unpleasant but does not typically pose serious health risks. Prevention of the condition is best.

Poison ivy, oak and sumac are among the plants that produce a resin called an urushiol that can cause an allergic rash. These plants belong to the plant genus known as Toxicodendron. The plants are found in different geographical distributions and are present throughout the U.S. except for desert areas, higher elevations (above 4,000 feet), Alaska, and Hawaii. (Poison ivy is most common in the eastern U.S. and poison oak and sumac in the Southeast.) The signs and symptoms produced by each of these plants cannot be distinguished from one another by their appearance. In addition, the same urushiols are also found in the mango, cashew, and ginkgo trees. In the case of mangos, peeling the fruit prevents dermatitis. People who press the whole fruit, including the rind, against their skin can develop a severe reaction around the mouth. Those downwind from burning vegetation containing one of the offending plants can also develop widespread allergic reactions.

Identifying poison ivy, oak, or sumac

Both poison ivy and poison oak have three leaflets, while poison sumac more commonly displays leaflets of five, seven, or more that angle upward toward the top of the stem. Although it is often recommended that people learn to recognize the poison ivy plant ("Leaves of three, leave them be"), in practice, this can be difficult, since poison ivy and its relatives are often mixed in with other vegetation and not noticed until after the rash has begun. Keeping the skin covered in situations in which exposure is hard to avoid is the best way to prevent the problem.

More than half the population can react to the poison ivy resin if they are exposed to it.

Picture of Poison Ivy Plant and Poison Ivy Skin Rash
Picture of Poison Ivy Plant and Poison Ivy Skin Rash

What are the signs and symptoms of the poison ivy, poison ask, and poison sumac rash?

Signs and symptoms are related both to the sensitivity of the individual as well as the severity of exposure. While over half of people are sensitive to poison ivy, oak, or sumac and will react by developing the characteristic rash, about 10%-15% of the population is highly sensitive and may have particularly severe symptoms or develop symptoms after a very mild exposure.

The rash usually starts one or two days after exposure, though the delay between contact and its onset can be longer, up to several days. This may lead to confusion over where the exposure took place. The first signs of the rash are curved lines of red, itchy bumps or blisters. These continue to appear for many days, even up to two to three weeks due to a slow reaction to absorbed urushiols and depending on how much resin touched the skin at a given point. This makes it seem as though the rash is "spreading," although the fluid in blisters is just part of the allergic reaction and contains no chemicals or bacteria. It also makes it appear that there may still be poison ivy in clothes and/or on pets. Although this is theoretically possible, repeated washing of these often produces no improvement.

In rare situations, the eyes, airway, and lungs may be affected if exposed to smoke from burning plants.

Poison ivy, oak, or sumac is not contagious, neither from one person to someone else nor from one part of the body to another.

Many references emphasize that animals can carry the poisonous resin. There's no doubt this is true, but its practical significance may be limited. The first sign of poison ivy, after all, is usually a curved line of rash on the skin. Your poison ivy is more likely to have come from a stem or leaf that dragged against the skin, not from your pet.

How is the dermatitis of poison ivy, oak, or sumac diagnosed?

The diagnosis is generally established upon observation of the typical rash in an area that could have been exposed to the plants, along with a history of potential exposure (such as weeding a garden or walking in the woods). No special tests are required for the diagnosis. In some cases, skin inflammation due to other causes (including allergic contact dermatitis or chemical irritation) may be mistaken for poison ivy, oak, or sumac since the rash may be similar.

What is the treatment for poison ivy, oak, and sumac dermatitis?

The best approach to poison ivy, oak, or sumac dermatitis is prevention. Washing with soap and water can help reduce the severity of the rash, but this is often impractical because it has to be done at once after exposure. (After 10 minutes, only 50% of the resin is removable, and by 30 minutes only 10%.)

Once it begins, the rash usually will clear on its own by 14-21 days. Treatment is directed at controlling the itching. Oral antihistamines, such as diphenhydramine (Benadryl), may help the itch somewhat, but often they do no more than make people drowsy. Cortisone creams, whether over the counter or by prescription, are only helpful if applied right away, before blisters appear, or much later, when the blisters have dried up. Compresses with Burow's solution (available without prescription) can help dry the ooze faster. Local anesthetic agents such as calamine lotion have also been shown to bring relief for some people. Oatmeal baths and cool compresses have also been recommended to help relieve symptoms.

When the rash is severe, such as when it affects the face or causes extensive blistering, oral steroids (for example, prednisone) can help produce rapid improvement. This course of therapy should be maintained, often in decreasing doses, for 10-14 days or even longer in some cases, to prevent having the rash rebound and become severe again. Patients who are given a six-day pack of cortisone pills often get worse again when they complete it because the dose was too low and administered for too short a time.

Folklore, medical and otherwise, endorses many other agents, including aloe leaves, vinegar, baking soda, tea bags, and meat tenderizer as treatments for poison ivy and related plant poisonings. Though these remedies are generally harmless, they are of questionable value.

How can contact with poison ivy, oak, and sumac be prevented?

Poison ivy and its relatives are often hidden among other vegetation. Even if you know exactly what they look like, it is very hard to avoid coming in contact with them. Although wearing long pants and long sleeves in warm weather may be uncomfortable, it is important to do so when you might be in contact with plants you can't see, whether you are gardening in the backyard or hiking in the woods. So-called "barrier creams" may help a bit but are not very effective.

When pulling up weeds, those who may be allergic should make sure to tuck sleeves into gloves at all times, since sleeves tend to ride up the forearms and leave wrists and forearms exposed. Vinyl gloves do not absorb urushiol well and are, therefore, more effective for prevention than fabric or leather gloves.

If you think you may have been exposed to poison ivy, wash the skin with cool water as soon as possible. After half an hour, however, this is no longer likely to prevent the reaction. As discussed above, washing pets and clothing may also be of limited help.

Attempts to desensitize people by giving them poison ivy by mouth or by injection were tried in the past but proved to be ineffective and potentially dangerous.


Rash 101: Introduction to Common Skin Rashes

 

View Skin Problems Slideshows

 

Adult Skin Problems Slideshow Pictures Pictures of Adult Skin Problems
Child Skin Problems Slideshow Pictures Pictures of Child Skin Problems
Gallery of Skin Problems Pictures and Images Collection Gallery of Skin Problems Pictures and Images Collection

 

Medical Authors: Alan Rockoff, MD, and Gary W. Cole, MD
Medical Editor: William C. Shiel Jr., MD, FACP, FACR

  • What are noninfectious, common rashes localized to a particular anatomical area?
  • How are common skin rashes diagnosed?
  • Scaly patches of skin produced by fungal or bacterial infection
  • Widely distributed rashes affecting large portions of the skin
  • What is the treatment for a rash?
  • Rashes At A Glance
  • Pictures of Adult Skin Problems - Slideshow View Adult Skin Problems Slideshow
  • Pictures of Child Skin Problems - Slideshow View Child Skin Problems Slideshow
  • Gallery of Skin Problems Pictures and Images CollectionView Gallery of Skin Problems Pictures and Images
  • Patient Discussions: Rash - Symptoms
  • Patient Discussions: Rash - Effective Treatments
  • Find a local Dermatologist in your town

 

What are noninfectious, common rashes localized to a particular anatomical area?

Common, noninfectious rashes are listed below. Since these conditions are not caused by infectious organisms, it is reasonable to attempt to treat them with over-the-counter 1% hydrocortisone cream for a week or so prior to seeking medical attention.

Seborrheic dermatitis: Seborrheic dermatitis is the single most common rash affecting adults. It produces a red, scaling eruption that characteristically affects the scalp, forehead, brows, cheeks, and external ears.

Atopic dermatitis: Atopic dermatitis, often called eczema, is a common disorder of childhood which produces red, itchy, weeping rashes on the inner aspects of the elbows and in back of the knees as well as the cheeks, neck, wrists, and ankles. It is commonly found in patients who also have asthma and hay fever.

 

Contact dermatitis: Contact dermatitis is a rash that is brought on either by contact with a specific chemical to which the patient is uniquely allergic or with a substance that directly irritates the skin. Some chemicals are both irritants and allergens. This rash is also occasionally weepy and oozy and affects the parts of the skin which have come in direct contact with the offending substance. Common examples of contact dermatitis caused by allergy are poison ivy or poison oak (same chemical, different plant) and reactions to costume jewelry containing nickel.

Diaper rash: This is a common type of contact dermatitis that occurs in most infants who wear diapers when feces and urine are in contact with skin for too long.

Stasis dermatitis: This is a weepy, oozy dermatitis that occurs on the lower legs of individual who have chronic swelling because of poor circulation in veins.

Psoriasis: This bumpy scaling eruption never weeps or oozes and tends to occur on the scalp, elbows, and knees. It leads to silvery flakes of skin that scale and fall off.

Nummular eczema: This is a weepy, oozy dermatitis that tends to occur a coin-shaped plaques in the winter time and is associated with very dry skin.

How are common skin rashes diagnosed?

The term rash has no precise meaning but often is used to refer to a wide variety of skin disorders. In normal conversation, a rash is any inflammatory condition of the skin. Dermatologists have developed various terms to describe skin rashes. The first requirement is to identify a primary, most frequent feature. Then, other characteristics of the rash are noted including density, color, size, consistency, tenderness, shape, and perhaps temperature. The configuration of the rash is described using adjectives such as "circular," "ring-shaped," "linear," and "snake-like."

Finally, the distribution of the rash on the body can be very useful in diagnosis since many skin diseases have a predilection to appear in certain body areas. Although certain findings may be a very dramatic component of the skin disorder, they may be of limited value in producing an accurate diagnosis. These include findings such as ulcers, scaling, and scabbing. Using this framework, it is often possible to develop a small listing of the possible diseases to be considered. Below is a short discussion of some common categories of skin rashes:

  • Noninfectious, common rashes localized to a particular anatomical areas
  • Rashes produced by fungal or bacterial infection
  • Widely distributed rashes affecting large portions of the skin

Although most rashes are seldom signs of immediate impending doom, self-diagnosis is not usually a good idea. Rashes that quickly resolve are generally not dangerous. Proper evaluation of a skin rash requires a visit to a doctor or other health-care professional.

Scaly patches of skin produced by fungal or bacterial infection

When infections appear as rashes, the most common culprits are fungal or bacterial infections.

Fungal infections: Fungal infections are fairly common but don't appear nearly as often as rashes in the eczema category. Perhaps the most common diagnostic mistake made by both patients and non-dermatology physicians is to almost automatically call scaly rashes "a fungus." For instance, someone with several scaly spots on the arms, legs, or torso is much more likely to have a form of eczema or dermatitis than actual ringworm (the layman's term for fungus). Likewise, yeasts are botanically related to fungi and can cause skin rashes. These tend to affect folds of skin (like the skin under the breasts or the groin). They look fiery red and have pustules around the edges. As is the case with ringworm, many rashes that are no more than eczema or irritation get labeled "yeast infections."

Fungus and yeast infections have little to do with hygiene -- clean people get them, too. Despite their reputation, fungal rashes are not commonly caught from dogs or other animals, nor are they easily transmitted in gyms, showers, pools, or locker rooms. In most cases, they are not highly contagious between people either.

Treatment is usually straightforward. Many effective antifungal creams can be bought at the drugstore without a prescription, including 1% clotrimazole (Lotrimin, Mycelex) and 1% terbinafine (Lamisil). In extensive cases, or when toenails are involved, oral terbinafine may be useful.

 

If a fungus has been repeatedly treated without success, it is worthwhile considering the possibility that it was never really a fungus to begin with but rather a form of eczema that should be treated entirely differently. A fungal infection can be independently confirmed by performing a variety of simple tests.

Bacterial infections: The most common bacterial infection of the skin is impetigo. Impetigo is caused by staph or strep germs and is much more common in children than adults. Eruptions caused by bacteria are often pustular (the bumps are topped by pus) or may be plaque-like and quite painful (cellulitis). Again, poor hygiene plays little or no role. Nonprescription antibacterial creams like bacitracin (Neosporin) are not very effective. Oral antibiotics or prescription-strength creams like mupirocin (Bactroban) are usually needed.

Widely distributed rashes affecting large portions of the skin

Outbreaks of this sort are usually either viral or allergic.

Viral rash: While viral infections of the skin itself, like herpes or shingles (a cousin of chickenpox), are mostly localized to one part of the body, viral rashes are more often symmetrical and everywhere. Patients with such rashes may or may not have other viral symptoms like coughing, sneezing, or stomach upset (nausea). Viral rashes usually last a few days to a week and go way on their own. Treatment is directed at relief of itch, if there is any.

Other rashes

Hives or "welts" (urticaria) are itchy, red bumps that come and go rapidly over six to eight hours on various parts of the body. Most hives run their course and disappear as mysteriously as they came. Heat rash is a skin irritation caused by excessive sweating during hot, humid weather. It can occur at any age but is most common in young children. Heat rash looks like a red cluster of pimples or small blisters. It is more likely to occur on the neck and upper chest, in the groin, under the breasts, and in elbow creases.

 

What is the treatment for a rash?

Most rashes are not dangerous to a person or people in the vicinity (unless they are part of an infectious disease such as chickenpox). Many rashes last a while and get better on their own. It is therefore not unreasonable to treat symptoms like itchy and/or dry skin for a few days to see whether the condition gets milder and goes away.

 

Nonprescription (over-the-counter) remedies include

  • anti-itch creams containing camphor, menthol, pramoxine (Itch-X, Sarna Sensitive), or diphenhydramine (Benadryl);
  • antihistamines like diphenhydramine, chlorpheniramine (Chlor-Trimeton), or loratadine (Claritin, Claritin RediTabs, Alavert); and cetirizine (Zyrtec);
  • moisturizing lotions.

If these measures do not help, or if the rash persists or becomes more widespread, a consultation with a general physician or dermatologist is advisable.

There are many, many other types of rashes that we have not covered in this article. So, it is especially important, if you have any questions about the cause or treatment of a rash, to contact your doctor. This article, as the title indicates, is just an introduction to common skin rashes.

A word on smallpox vaccination in patients with rashes

People with atopic dermatitis or eczema should not be vaccinated against smallpox, whether or not the condition is active. Patients with atopic dermatitis are more susceptible to having the virus spread on their skin, which can lead to a serious, even life-threatening condition called eczema vaccinatum. In the case of other rashes, the risk of complications is much less. Consult your doctor about the smallpox vaccine.

Rashes At A Glance
  • Rash is not a specific diagnosis. It is instead a general term that means an outbreak of skin inflammation and discoloration that change the way the skin looks and feels.
  • Common rashes include eczema, poison ivy, and heat rash.
  • Infections that cause rashes include fungal, bacterial, or viral infection.
  • Over-the-counter products to combat infection or itch may be helpful with the proper diagnosis.
  • Rashes lasting more than a few days that are unexplained should be evaluated by a doctor.


Skin Test For Allergy

 

View Slideshow Pictures

 

10 Common Allergy Triggers Slideshow Pictures 10 Common Allergy Triggers
Take the Quiz on Allergies Allergies Quiz: Test Your Medical IQ
Nasal Allergy Relief Slideshow Pictures Nasal Allergy Relief Slideshow Pictures

 

  • What is a skin test for allergy?
  • How is an allergy skin test done?
  • What is a positive skin test?
  • Can you give an example of a skin test?
  • What are the advantages of skin tests?
  • Is there danger to a skin test?
  • What is done if a skin test can't be done?
  • Find a local Asthma & Allergy Specialist in your town

What is a skin test for allergy?

This is a test done on the skin to identify the allergy substance (the allergen) that is the trigger for an allergic reaction.

How is an allergy skin test done?

A small amount of the suspected allergy-provoking substance (the allergen) is placed on the skin. The skin is then gently scratched through the small drop with a special sterile needle. An allergy skin test is also called a scratch test.

What is a positive skin test?

If the skin reddens and, more importantly, if it swells, then the test is read as positive and allergy to that substance is considered probable.

Can you give an example of a skin test?

If a specific food allergy is suspected, a skin test uses a dilute extract of the suspect food. A small drop of this particular liquid extract is placed on the skin of the forearm or back. This underlying skin is gently scratched through the small drop with a special sterile needle. If the skin reddens and, more importantly, if it swells, then the test is read as positive. If there is no reaction, it is read as negative.

If the skin test is positive, it implies that the patient has a type of antibody (IgE antibody) on specialized cells in the skin that release histamine to cause redness and itching. (These cells are called mast cells and the IgE antibody bound to them is specific to the food being tested.)

What are the advantages of skin tests?

Skin tests are rapid, simple, and relatively safe. They can be very helpful in specifically identifying causes of allergies.

Is there danger to a skin test?

In some extremely allergic patients who have severe reactions called anaphylactic reactions, skin testing cannot be used because it could evoke a dangerous reaction. Skin testing also cannot be done on patients with extensive eczema.

What is done if a skin test can't be done?

For these patients a doctor may use special blood tests, such as the RAST and the ELISA. These tests measure the presence of specific types of IgE in the blood.

These tests may cost more than skin tests, and results are not available immediately. As with skin testing, positive RAST and ELISA tests do not by themselves necessarily make the final diagnosis.


Alopecia Areata

 

View Hair Loss Slideshow Pictures
Hair Loss Slideshow Pictures Hair Loss Slideshow Pictures
Hair and Scalp Slideshow Pictures Hair and Scalp Slideshow Pictures

 

Medical Author: Zoe Diana Draelos, MD, PA
Medical Editor: William C. Shiel Jr., MD, FACP, FACR

  • What is alopecia areata?
  • What causes alopecia areata?
  • What are the different patterns of alopecia areata?
  • Who is affected by alopecia areata?
  • How is alopecia areata diagnosed?
  • How is alopecia areata treated?
  • Alopecia Areata At A Glance
  • Patient Discussions: Alopecia Areata - Symptoms
  • Patient Discussions: Alopecia Areata - Effective Treatments
  • Find a local Dermatologist in your town

What is alopecia areata?

Alopecia areata is a hair-loss condition which usually affects the scalp. It can, however, sometimes affect other areas of the body. Hair loss tends to be rather rapid and often involves one side of the head more than the other.

Alopecia areata affects both males and females. This type of hair loss is different than male-pattern baldness, an inherited condition.

What causes alopecia areata?

Current evidence suggests that alopecia areata is caused by an abnormality in the immune system. This particular abnormality leads to autoimmunity. As a result, the immune system attacks particular tissues of the body. In alopecia areata, for unknown reasons, the body's own immune system attacks the hair follicles and disrupts normal hair formation. Biopsies of affected skin show immune cells inside of the hair follicles where they are not normally present. What causes this is unknown. Alopecia areata is sometimes associated with other autoimmune conditions such as allergic disorders, thyroid disease, vitiligo, lupus, rheumatoid arthritis, and ulcerative colitis. Sometimes, alopecia areata occurs within family members, suggesting a role of genes and heredity.

What are the different patterns of alopecia areata?

The most common pattern is one or more spots of hair loss on the scalp. There is also a form of more generalized thinning of hair referred to as diffuse alopecia areata throughout the scalp. Occasionally, all of the scalp hair is lost, a condition referred to as alopecia totalis. Less frequently, the loss of all of the hairs on the entire body, called alopecia universalis, occurs. Sometimes the hair loss can involve the male beard, a condition known as alopecia areata barbe.

Who is affected by alopecia areata?

Alopecia areata tends to occur most often in children, teens, and young adults. However, it can also affect older individuals and rarely toddlers. Alopecia areata in not contagious. It should not be confused with the hair shedding that may occur following the discontinuation of hormonal estrogen and progesterone therapies for birth control or the hair shedding associated with the end of pregnancy.

How is alopecia areata diagnosed?

The characteristic finding of alopecia areata is the exclamation point hair. These unusual hairs can be found in areas of hair loss. They are visible with a hand lens as short, broken off hairs that are narrower closer to the scalp (appearing like an exclamation point). A biopsy of the scalp is sometimes necessary for a diagnosis.

How is alopecia areata treated?

In approximately 50% of patients, hair will regrow within a year without any treatment. The longer the period of time of hair loss, the less likelihood that the hair will regrow. A variety of treatments can be tried. Steroid injections, creams, and shampoos (such as clobetasol or fluocinonide) for the scalp have been used for many years. Other medications include minoxidil, irritants (anthralin or topical coal tar), and topical immunotherapy (cyclosporine), each of which are sometimes used in different combinations.

A study reported in the journal Archives of Dermatology (vol. 134, 1998;1349-52) showed effectiveness of aromatherapy essential oils (cedarwood, lavender, thyme, and rosemary oils) in some patients. As with many chronic disorders for which there is no single treatment, a variety of remedies are promoted which in fact have no benefit. There is no known effective method of prevention, although the elimination of emotional stress is felt to be helpful. No drugs or hair-care products have been associated with the onset of alopecia areata. Much research remains to be completed on this complex condition.

Alopecia Areata At A Glance
  • Alopecia areata is a hair-loss condition which usually affects the scalp.
  • Alopecia areata typically causes one or more patches of hair loss.
  • Alopecia areata tends to affect younger individuals, both male and female.
  • An autoimmune disorder, in which the immune system attacks hair follicles, is believed to cause alopecia areata.
  • For most patients, the condition resolves without treatment within a year, but hair loss is sometimes permanent.
  • A number of treatments are known to aid in hair regrowth. Multiple treatments may be necessary, and none consistently works for all patients.
  • Many treatments are promoted which have not proven to be of benefit.


Alpha-1 Antitrypsin Deficiency

 

Hidden Home Hazards That Can Harm Your Lungs
Hidden Home Hazards That Can Harm Your Lungs
Energy-Boosting Foods for COPD Slideshow Pictures Energy-Boosting Foods for COPD
Worst Smog Cities in America Slideshow Worst Smog Cities in America Slideshow

 

  • What is alpha-1 antitrypsin deficiency?
  • What are the signs and symptoms of lung disease caused by alpha-1 antitrypsin deficiency?
  • How common is alpha-1 antitrypsin deficiency?
  • What genes are related to alpha-1 antitrypsin deficiency?
  • How do people inherit alpha-1 antitrypsin deficiency?
  • Where can I find information about treatment for alpha-1 antitrypsin deficiency?
  • What other names do people use for alpha-1 antitrypsin deficiency?

What is alpha-1 antitrypsin deficiency?

Alpha-1 antitrypsin deficiency is an inherited disorder that can cause lung disease in adults and liver disease in adults and children.

What are the signs and symptoms of lung disease caused by alpha-1 antitrypsin deficiency?

The first signs and symptoms of lung disease caused by alpha-1 antitrypsin deficiency usually appear between ages 20 and 50. The earliest symptoms are:

  • shortness of breath following mild activity,
  • reduced ability to exercise, and
  • wheezing.

Other signs and symptoms can include:

  • unintentional weight loss,
  • recurring respiratory infections,
  • fatigue,
  • rapid heartbeat upon standing, and
  • vision abnormalities.

Advanced lung disease leads to emphysema, in which small air sacs in the lungs (alveoli) are damaged. Characteristic features of emphysema include:

  • difficulty breathing,
  • a hacking cough, and
  • a barrel-shaped chest.

Smoking or exposure to tobacco smoke accelerates the appearance of symptoms and damage to the lungs.

About 10 percent of infants and 15 percent of adults with alpha-1 antitrypsin deficiency have liver damage. Signs of liver disease can include:

  • a swollen abdomen,
  • swollen feet or legs, and
  • yellowing of the skin and whites of the eyes (jaundice).

In rare cases, alpha-1 antitrypsin deficiency also causes a skin condition known as panniculitis, which is characterized by hardened skin with painful lumps or patches. Panniculitis varies in severity and can occur at any age.

How common is alpha-1 antitrypsin deficiency?

Alpha-1 antitrypsin deficiency occurs worldwide, but its prevalence varies by population. For example, in Scandinavia this disorder affects 1 in 1,500 to 3,000 individuals, but it is less common in Asian and black populations. In North America, alpha-1 antitrypsin deficiency affects 1 in 5,000 to 7,000 people.

What genes are related to alpha-1 antitrypsin deficiency?

Mutations in the SERPINA1 gene cause alpha-1 antitrypsin deficiency.

The SERPINA1 gene provides instructions for making a protein called alpha-1 antitrypsin. This protein protects the body from being damaged by a powerful enzyme called neutrophil elastase. Neutrophil elastase is released from white blood cells to fight infection, but it can attack normal tissues (such as lung tissue) if not carefully controlled by alpha-1 antitrypsin. Mutations in the SERPINA1 gene can lead to a shortage (deficiency) of alpha-1 antitrypsin protein or an abnormal form of the protein that cannot control neutrophil elastase. Uncontrolled, neutrophil elastase destroys alveoli, which can lead to emphysema. The abnormal form of alpha-1 antitrypsin can also accumulate in the liver and may damage this organ.

How do people inherit alpha-1 antitrypsin deficiency?

This condition is inherited in an autosomal codominant pattern. Codominance means that two different versions of the gene may be expressed, and both versions contribute to the genetic trait.

The most common version (allele) of the SERPINA1 gene, called M, produces normal levels of the alpha-1 antitrypsin protein. Most people have two copies of the M allele (MM) in each cell. Other versions of the SERPINA1 gene lead to reduced levels of alpha-1 antitrypsin. For example, the S allele produces moderately low levels of this enzyme, and the Z allele produces very little alpha-1 antitrypsin. Individuals with two copies of the Z allele (ZZ) in each cell are likely to have alpha-1 antitrypsin deficiency. Those with the SZ combination have an increased risk of developing lung disorders (such as emphysema), particularly if they smoke.

Worldwide, about 161 million people have one copy of the S or Z allele and one copy of the M allele in each cell (MS or MZ). Individuals with a MS (or SS) combination usually produce enough alpha-1 antitrypsin to protect the lungs. People with MZ alleles, however, have a slightly increased risk of impaired lung or liver function.

Where can I find information about treatment for alpha-1 antitrypsin deficiency?

These resources address the management of alpha-1 antitrypsin deficiency and may include treatment providers.

  • Gene Review: Alpha-1-Antitrypsin Deficiency
  • Genetic Alliance

What other names do people use for alpha-1 antitrypsin deficiency?

  • AAT
  • AATD
  • alpha-1 proteinase inhibitor
  • alpha-1 related emphysema
  • genetic emphysema
  • hereditary pulmonary emphysema
  • inherited emphysema

How Do People Inherit Alpha Thalassemia?

The inheritance of alpha thalassemia is complex. Each person inherits two alpha-globin alleles from each parent. If both parents are missing at least one alpha-globin allele, their children are at risk of having Hb Bart syndrome, HbH disease, or alpha thalassemia trait. The precise risk depends on how many alleles are missing and which combination of the HBA1 and HBA2 genes is affected.


Alpha Thalassemia

 

View Birth Control Slideshow Pictures
Take the Blood and Bleeding Disorders Quiz! Take the Blood and Bleeding Disorders Quiz!
  • Alpha thalassemia facts*
  • What is alpha thalassemia?
  • What are the symptoms of alpha thalassemia?
  • What are the types of alpha thalassemia?
  • How common is alpha thalassemia?
  • What genes are related to alpha thalassemia?
  • How do people inherit alpha thalassemia?
  • Find a local Hematologist in your town

Alpha Thalassemia Facts*

*Alpha thalassemia facts Medically Edited by:

Melissa Conrad Stöppler, MD

  • Alpha thalassemia is a blood disorder that reduces the production of hemoglobin, the protein in red blood cells that carries oxygen to cells throughout the body.
  • There are two types of alpha thalassemia, hemoglobin Bart hydrops fetalis syndrome or Hb Bart syndrome (the more severe form) and HbH disease.
  • Alpha thalassemia also occurs frequently in people from Mediterranean countries, North Africa, the Middle East, India, and Central Asia.
  • Alpha thalassemia typically results from deletions involving the HBA1 and HBA2 genes.
  • People who have alpha thalassemia trait can have mild anemia. However, many people with this type of thalassemia have no signs or symptoms.
  • Treatments for thalassemias depend on the type and severity of the disorder.

 

What is alpha thalassemia?

Alpha thalassemia is a blood disorder that reduces the production of hemoglobin. Hemoglobin is the protein in red blood cells that carries oxygen to cells throughout the body.

What are the symptoms of alpha thalassemia?

In people with the characteristic features of alpha thalassemia, a reduction in the amount of hemoglobin prevents enough oxygen from reaching the body's tissues. Affected individuals also have a shortage of red blood cells (anemia), which can cause pale skin, weakness, fatigue, and more serious complications.

What are the types of alpha thalassemia?

Two types of alpha thalassemia can cause health problems. The more severe type is known as hemoglobin Bart hydrops fetalis syndrome or Hb Bart syndrome. The milder form is called HbH disease.

Hb Bart syndrome is characterized by hydrops fetalis, a condition in which excess fluid builds up in the body before birth. Additional signs and symptoms can include severe anemia, an enlarged liver and spleen (hepatosplenomegaly), heart defects, and abnormalities of the urinary system or genitalia. As a result of these serious health problems, most babies with this condition are stillborn or die soon after birth. Hb Bart syndrome can also cause serious complications for women during pregnancy, including dangerously high blood pressure with swelling (preeclampsia), premature delivery, and abnormal bleeding.

HbH disease causes mild to moderate anemia, hepatosplenomegaly, and yellowing of the eyes and skin (jaundice). Some affected individuals also have bone changes such as overgrowth of the upper jaw and an unusually prominent forehead. The features of HbH disease usually appear in early childhood, and affected individuals typically live into adulthood.

 

How Common Is Alpha Thalassemia?

Alpha thalassemia is a fairly common blood disorder worldwide. Thousands of infants with Hb Bart syndrome and HbH disease are born each year, particularly in Southeast Asia. Alpha thalassemia also occurs frequently in people from Mediterranean countries, North Africa, the Middle East, India, and Central Asia.

What Genes Are Related to Alpha Thalassemia

Alpha thalassemia typically results from deletions involving the HBA1 and HBA2 genes. Both of these genes provide instructions for making a protein called alpha-globin, which is a component (subunit) of hemoglobin.

People have two copies of the HBA1 gene and two copies of the HBA2 gene in each cell. Each copy is called an allele. For each gene, one allele is inherited from a person's father, and the other is inherited from a person's mother. As a result, there are four alleles that produce alpha-globin. The different types of alpha thalassemia result from the loss of some or all of these alleles.

Hb Bart syndrome, the most severe form of alpha thalassemia, results from the loss of all four alpha-globin alleles. HbH disease is caused by a loss of three of the four alpha-globin alleles. In these two conditions, a shortage of alpha-globin prevents cells from making normal hemoglobin. Instead, cells produce abnormal forms of hemoglobin called hemoglobin Bart (Hb Bart) or hemoglobin H (HbH). These abnormal hemoglobin molecules cannot effectively carry oxygen to the body's tissues. The substitution of Hb Bart or HbH for normal hemoglobin causes anemia and the other serious health problems associated with alpha thalassemia.

Two additional variants of alpha thalassemia are related to a reduced amount of alpha-globin. Because cells still produce some normal hemoglobin, these variants tend to cause few or no health problems. A loss of two of the four alpha-globin alleles results in alpha thalassemia trait. People with alpha thalassemia trait may have unusually small, pale red blood cells and mild anemia. A loss of one alpha-globin allele is found in alpha thalassemia silent carriers. These individuals typically have no thalassemia-related signs or symptoms.

How Do People Inherit Alpha Thalassemia?

The inheritance of alpha thalassemia is complex. Each person inherits two alpha-globin alleles from each parent. If both parents are missing at least one alpha-globin allele, their children are at risk of having Hb Bart syndrome, HbH disease, or alpha thalassemia trait. The precise risk depends on how many alleles are missing and which combination of the HBA1 and HBA2 genes is affected.

 


<< Start < Prev 11 12 13 14 15 16 17 18 19 20 Next > End >>
(Page 17 of 25)
Share
 
Ruai Pharm Stats