Common Allergies

A llergies pose a significant and serious health problem in this country. According to conservative estimates, nearly 15 million Americans are plagued by hay fever and 10 million have asthma. Twelve million more Americans suffer from such allergies as eczema and hives, not to mention allergic reactions to food, drugs, and insect stings. Most of these disorders have a hereditary component and tend to run in families.

What Is An Allergic Reaction?

Basically, an allergic reaction occurs whenever the immune system overreacts to a seemingly harmless substance. Known as allergens, these substances include pollen, mold, house dust, mites, animal saliva and dander (skin shed by cats, dogs, or rabbits), feathers (such as those used in feather pillows), certain foods and drugs, and insect stings.

Allergens are usually absorbed into the body by way of the skin, nasal passages, lungs, or digestive tract. Once inside the body, allergens stimulate the lymphocytes (small white blood cells) to produce what are known as allergic antibodies. The reaction between the allergen and these antibodies, which are attached to certain special cells (mast cells), leads to inflammation of the nose, eyes, lungs, and the digestive tract. A stuffy nose, sneezing, wheezing, skin rash, watery eyes, abdominal cramps, and nausea are some of the most common results.

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Asthma

Although asthma is a common condition that affects all age groups, one-third of all cases occur in children under 10 years old. This means that approximately three million children in the fifth grade and below suffer from this disorder. Not surprisingly, asthma accounts for more school absences than any other chronic childhood illness.

The chief symptoms of asthma include coughing, wheezing, and shortness of breath. An asthma attack may be brought on by any of the previously mentioned allergens or by infections in the sinuses or bronchial tubes. Emotional stress, hormonal changes, irritants such as cigarette smoke, changes in temperature and humidity, and exercise also may trigger an asthmatic episode.

Asthma attacks may begin suddenly with the onset of severe symptoms, or start slowly with a gradually increasing difficulty in breathing. A typical acute asthmatic attack is marked by wheezing, labored breathing, tightness in the chest, and a dry cough. Asthma attacks may produce a feeling of suffocation and an inability to speak without frequent pauses to catch the breath. The victim may also have a rapid pulse, sweat profusely, and turn blue.

Treatment for asthma usually consists of removing the offending allergen or irritant and administering medications that reduce inflammation and open the air passages. For patients with daily symptoms, inhaled steroid drugs such as Azmacort, Beclovent, Vanceril, and AeroBid are frequently prescribed, as are cromolyn sodium (Intal), nedocromil sodium (Tilade), theophylline (Theo-Dur, Uniphyl), and albuterol (Proventil, Ventolin). For patients hospitalized with a serious attack, airway-opening drugs may be given intravenously.

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Hay Fever

Allergic rhinitis (hay fever) can be brought on at certain seasons by the airborne pollens of trees, grass, and weeds. Other allergens cause hay fever all year. These year-round troublemakers include molds, dust mites, and animal dander.

Hay fever symptoms include sneezing, watery eyes, runny nose, nasal congestion, and an itchy palate and throat. Hay fever can also be accompanied by conjunctivitis (itchy, swollen eyes), malaise, headache, and sinus pain.

The treatment of hay fever consists of removing the environmental antigen, if possible, and implementing drug therapy and immunotherapy (allergy shots). The newer antihistamines, such as terfenadine (Seldane) and loratadine (Claritin), cause less drowsiness and dryness. Topical intranasal steroids, such as flunisolide (Nasalide), beclomethasone (Beconase, Vancenase), and triamcinolone (Nasacort), reduce inflammation and may eliminate the need for oral antihistamines and decongestants.
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Hives and Angioedema

Hives (urticaria) are itchy, red, swollen patches of skin that appear suddenly. Although they may vanish within one to two hours, they can last as long as two days. They frequently occur in clusters, with new clusters forming as others fade. They do not leave scars.

Hives may have an allergic or non-allergic cause; and the exact culprit usually cannot be determined. They are often triggered by a food or a drug. Common foods that cause hives include nuts, shellfish, peanuts, and eggs. Drugs that typically produce hives include penicillin, sulfa, anticonvulsants, aspirin, and nonsteroidal anti-inflammatory drugs (NSAIDs). Tight-fitting clothing that scratches or rubs the skin, activities that increase the body's temperature (warm baths, hot tubs, exercise, or fever), and exposure to cold or sunlight may all cause hives in susceptible individuals.

Angioedema is a condition like hives that occurs in the deeper layers of the skin, most often in the hands, feet, and face. Certain types of hereditary angioedema may cause fatal swelling of the larynx.

Hives and angioedema are treated by avoiding whatever substance has provoked the outbreak, if it can be identified. Antihistamines such as hydroxyzine (Atarax), diphenhydramine (Benadryl), loratadine (Claritin), astemizole (Hismanal), terfenadine (Seldane) and clemastine (Tavist) are used to treat daily occurrences. Oral corticosteroids are considered a last resort.

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Dermatitis

Atopic dermatitis is a form of eczema that often begins in early childhood. It is frequently associated with allergic rhinitis or asthma. Half the cases disappear by adulthood.

We don't know what causes atopic dermatitis. The symptoms in infants include itchy red patches on the face, torso, and lower parts of the limbs. These patchy areas crust, scale, and ooze. A child between the ages of two and four may develop clusters of red or flesh-colored scaly patches or bumps on the elbows, knee creases, ankles, neck, wrists, and feet. The rash becomes more concentrated during adolescence, appearing on the sides of the neck, hands, and face, and the skin becomes more thickened.

People with atopic dermatitis are prone to bacterial skin infections that produce itching and redness. Oozing, crusting ulcers may also occur in some cases.

The goal of treatment is to eliminate the itching. Therapeutic measures typically include application of lubricants and moisturizers while the skin is damp after bathing, plus use of topical corticosteroids, such as fluocinolone acetonide (Synalar). Oral antihistamines such as hydroxyzine (Atarax) and diphenhydramine (Benadryl) help ease the itching.

Allergic contact dermatitis may be caused by poison ivy, oak, or sumac, as well as by exposure to nickel, chrome, mercury, certain cosmetics, and drugs applied to the skin.

Poison ivy produces redness, bumps, and blisters, as well as swelling after the initial contact. The blisters burst after a few days, releasing a watery liquid, and healing begins. Treatment includes trying to prevent a rash by promptly washing the affected area with soap and water--within five minutes of contact, if possible. If a rash develops, wet, cold compresses and steroid ointments may be advised. Oral steroids may be necessary for severe cases.
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Stings and Anaphylaxis

Stinging insect allergies result when a sensitive individual is stung by a bee, wasp, hornet, yellow jacket, or fire ant. The reaction usually occurs soon after the initial sting and may include wheezing, generalized hives, angioedema, and a sharp drop in blood pressure. The victim may also go into shock and lose consciousness. If not treated immediately, severe reactions may be fatal.

Avoidance is the best strategy for someone with this type of sensitivity. Anyone who has an adverse reaction should consult an allergist for skin testing. Venom immunotherapy could be a lifesaver in the event of a future sting. Sensitive individuals should have injectable epinephrine (EpiPen, Ana-Kit) available in case of an attack.

Anaphylaxis is a severe and potentially life-threatening allergic reaction distinguished by the sudden onset of hives or angioedema, respiratory distress, and a drop in blood pressure. The reaction is caused in susceptible individuals by a variety of allergens, including vaccines; penicillin and other antibiotics; diagnostic chemicals; insect venom; polysaccharides; food (including berries, nuts, seafood, and egg whites); aspirin; and nonsteroidal anti-inflammatory agents. Penicillin is by far the most common culprit. Exercise may also induce anaphylaxis in some people.

Symptoms of anaphylaxis include feelings of impending doom or fright, itching of the skin, nasal congestion and coughing, hives and swelling of tissues in the lips or larynx, wheezing, shortness of breath, low blood pressure, and loss of consciousness. The person's eyes may also itch, swell, and tear. Other symptoms include change of voice, hoarseness, itching of the mouth and throat, sneezing, chest pain and tightness, redness of the skin, cramping of the uterus, a feeling of warmth and flushing, a need to urinate, abdominal cramps, nausea, vomiting, and diarrhea.

Anaphylaxis is an emergency condition that requires an immediate injection of epinephrine. Emergency injection devices such as EpiPen or Ana-Kit could be lifesaving if available for use in an unexpected attack. In any event, if you experience any of these symptoms, seek medical help right away.

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