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    Allergy Terms Glossary

    Allergen: A substance the body thinks is harmful, which triggers an allergic reaction.

    Allergist: A doctor who specializes in allergy-related conditions.

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    Anaphylaxis : A severe, life-threatening reaction marked by trouble breathing, a drop in blood pressure, along with hives, stomach cramps, or belly pain. In severe cases, a person will go into shock. If anaphylactic shock isn't treated immediately, it can be fatal.

    Antihistamines : These drugs block histamine, a chemical the body releases during an allergic reaction. The meds ease symptoms like itching, sneezing, and runny nose.

    Anti-inflammatory drugs: Medications that calm the symptoms of inflammation, such as pain, swelling, and redness.

    Bronchodilator medication: Drugs that relax tight muscles around lung airways. This makes it easier to breathe.

    Bronchitis : An inflammation of the airways. Symptoms include a persistent cough and phlegm. It usually affects smokers and crops up in locations with high air pollution. It can also be caused by an infection, both viral or bacterial.

    Corticosteroids: A steroid that contains anti-inflammatory drugs that treat the itching and swelling tied to some allergic reactions.

    Decongestants : Medications that shrink swollen nasal membranes, which eases congestion and mucus, and makes it easier to breathe.

    Elimination diet: A plan that has you stop eating foods that might be causing your allergic reactions.

    Epinephrine : A medication that treats severe allergic reactions immediately. Also known as adrenaline, this relaxes tightened muscles around the airways, which makes it easier to breathe.

    HEPA: High-efficiency particulate air (HEPA). This type of filter removes tiny airborne particles by pushing them through screens with microscopic pores.

    Histamine: A chemical released by the immune system after it's exposed to an allergen. Histamine causes allergy symptoms such as runny nose, sneezing, and itching.

    Hypoallergenic: Products that have as few allergens as possible.

    Immunotherapy: Your doctor may call these “allergy shots.” They slowly expose you to an allergen (usually by injection, but drops may also be placed under the tongue). They’re meant to raise your tolerance to allergy-causers like pollen, dander, insect stings, or some foods. The FDA has also approved under-the-tongue immunotherapy tablets that treat hay fever.

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