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    Allergies Health Center

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    Top Allergy Terms


    Dander, animal: Tiny scales shed from animal skin or hair. It floats in the air, settles on surfaces, and makes up much of household dust. Pet dander is a classic cause of allergic reactions.

    Decongestant: Medication that shrinks swollen nasal tissues to relieve symptoms like swelling, congestion, and mucus.

    Dermatitis : Inflamed skin, either due to an allergic reaction or direct contact with an irritating substance. Symptoms include redness, itching, and sometimes blistering.

    Drug allergy: An allergic reaction to a specific medication, like penicillin.

    Dust mites : Microscopic insects that live in household dust and are common allergens. Dust mites live on dead skin cells. You’ll find them in mattresses, pillows, carpets, curtains, and furniture.

    Elimination diet: When you temporarily stop eating certain foods to rule them out as a cause of your allergy symptoms. It could be a permanent change if you have celiac disease or a long-lasting food allergy.

    ELISA (enzyme-linked immunosorbent assay): This blood test helps your doctor figure out what causes your allergy symptoms and how sensitive to them you are.

    Epinephrine : A form of adrenaline medication used to treat severe allergic reactions, like anaphylactic shock or insect stings. It’s available in a self-injectable form or a doctor can give you a shot.

    Food allergy : Your immune system reacts to a specific food that isn’t really a threat to your body.

    Hay fever : An allergic reaction to pollen from ragweed, grasses, and other plants whose pollen spreads on the wind.

    HEPA: Stands for high-efficiency particulate air (HEPA) filter. A filter, or gadget with this kind of filter, that cleans the air by forcing it through screens containing microscopic pores.

    Histamine: A naturally occurring substance that your immune system releases after it’s exposed to an allergen. Histamine is responsible for many of the symptoms of an allergy.

    Hives: See Urticaria.

    Hypoallergenic: Products made to contain the fewest possible allergens.

    Immune system: The body's main defense system. It protects us from infections and foreign substances.

    Immunotherapy: It’s a way to gradually increase your tolerance to the things that cause allergy symptoms (allergens). It works best for people who have symptoms more than 3 months out of the year. You can take it as shots, oral tablets, or drops.

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