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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

    Allergy Tips for Outdoor Living

    Try these tips to enjoy outdoor living, gardening, and hiking despite your allergies. Thick of It: Is the grass getting high? Wear a mask if you're mowing. Nothing fancy -- an inexpensive painter's mask works fine. High and Dry: Pollen counts are highest on hot, dry, windy days. Check the forecast before making plans. Good Scents, Bad Sense: Allergic to insect stings? Don't wear scented deodorants, perfumes, shampoos, or hair products. Carry an epi pen when hiking. Orange...

    Read the Allergy Tips for Outdoor Living 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 itching, sneezing, and a runny nose.

    Asthma : A long-term inflammatory lung disease. Symptoms include breathing problems, fatigue, headaches, 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 rash. It 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 rhinitis. Hay 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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