Dust mites: Microscopic insects that live in household dust and are common allergens. Dust mites live on dead skin cells and can be found in large numbers in mattresses, pillows, carpets, curtains, and furniture.
Elimination diet: A diet in which certain foods are temporarily discontinued from the diet to rule out the cause of allergy symptoms.
ELISA (enzyme-linked immunosorbent assay): Blood test used to identify the substances that are causing your allergy symptoms and to estimate a relative sensitivity.
Epinephrine: A form of adrenaline medication used to treat severe allergic reactions, such as anaphylactic shock or insect stings. It is available in a self-injectable form or can be injected by a health care provider.
Food allergy: Allergy that occurs when the immune system responds defensively to a specific food protein that is not otherwise harmful to the body.
Hay fever: Allergic reaction caused by the pollens of ragweed, grasses, and other plants whose pollen is spread by the wind.
HEPA: High-efficiency particulate air (HEPA) filter, which removes particles in the air by forcing it through screens containing microscopic pores.
Histamine: A naturally occurring substance that is released by the immune system after being exposed to an allergen. Histamine is responsible for many of the symptoms of an allergy.
Hives: See Urticaria.
Hypoallergenic: Products formulated to contain the fewest possible allergens.
Immune system: The body's defense system that protects us against infections and foreign substances.
Immunotherapy: Also called allergy desensitization or allergy shots; immunotherapy is given to increase a person's tolerance to the substances that provoke allergy symptoms (allergens). Allergy shots reduce your sensitivity to certain substances but do not cure allergies. They are usually recommended for people who suffer from allergies more than three months a year.
Latex: Also known as rubber or natural latex. Latex is a milky fluid derived from the rubber tree. It is used in a wide variety of consumer products, including rubber gloves, tubing, and rubber bands, for example.
Latex allergy: An allergy that develops after some sensitizing contact with latex.
Mast cell: A type of white blood cell that is involved in an allergic reaction. These cells release chemicals such as histamine.
Metered dose inhaler (MDI): Small aerosol canister in a plastic container that releases a burst of medication when pressed down from the top. Many asthma drugs are taken using a MDI.
Mold: Parasitic, microscopic fungi that float in the air like pollen. Mold is a common trigger for allergies and can be found in damp areas, such as basements or bathrooms, as well as in grass, leaf piles, hay, mulch, or under mushrooms.
Mold count: See Pollenand mold counts.
Myringotomy: Outpatient procedure in which small metal or plastic tubes are inserted through the eardrum to equalize pressure between the middle and outer ear.