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    Living With Allergies: A Glossary

    Allergen: A substance the body sees as harmful. In response, an allergic reaction is triggered.

    Allergist: A doctor who diagnoses and treats allergy-related conditions.

    Recommended Related to Allergies

    Living With Severe Allergies

    Allergies affect more than 50 million people in the United States -- the poor souls who sniffle, sneeze, and get all clogged up when face to face with the allergen (or allergens) that set them off. For many, allergies are seasonal and mild, requiring nothing more than getting extra tissue or taking a decongestant occasionally. For others, the allergy is to a known food, and as long as they avoid the food, no problem. But for legions of others adults, allergies are so severe it interferes with...

    Read the Living With Severe Allergies article > >

    Anaphylaxis : A life-threatening allergic reaction involving the entire body. It requires immediate medical attention.

    Antihistamines : Drugs that block histamine, a chemical the body releases during an allergic reaction. These meds ease symptoms like itchingsneezing, and a runny nose.

    Asthma : A long-term inflammatory lung disease. Symptoms include breathing problemsfatigueheadaches, and coughing. The triggers include allergens, an infection, exercise, cold air, or other things.

    Atopic dermatitis : See "Eczema."

    Bronchitis : An inflammation of the lung's airways. Symptoms include a persistent cough and phlegm. The condition usually affects smokers and people who live in places with lots of pollution.

    Contact dermatitis : An allergic reaction that happens after skin comes in contact with an allergen such as poison ivy, washing powders, perfumes, or other irritants.

    Dander: Small pieces of skin shed by an animal, similar to human dandruff. Proteins in dander are major causes of pet allergies.

    Decongestants : Medications that shrink swollen nasal membranes, relieving congestion and mucus and making it easier to breathe.

    Eczema : Chronic inflammation that causes a skin rashIt may be a reaction to an allergen. Symptoms include itching, crusting, blisters, and scaling. Atopic dermatitis is a type of eczema that gets worse after you come in contact with an allergen.

    Epinephrine : A drug used to immediately treat severe allergic reactions. Also known as adrenaline. Epinephrine causes an increase in blood pressure and heart rate.

    Inflammation: Redness, swelling, heat, and pain in a tissue. Such symptoms can be the result of an allergic reaction in the nose, lungs, or skin.

    Hay fever : Also known as allergic rhinitisHay fever is an inflammation of the mucous membranes in the nose. The condition often stems from allergies to pollen, dust, certain foods, and other substances. Symptoms include sneezing, itching, a runny nose, and nasal congestion.

    Histamine: A chemical released by the immune system after it's exposed to an allergen. It causes tissues to become swollen, inflamed, itchy, and red.

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