Glossary of Terms

Adenoids: Glands or lymphoid tissue in the upper part of the throat behind the nose.

Adenoidectomy: The surgical removal of adenoids which may help prevent blockage of the nasal passageways and eustachian tubes. This may help to reduce recurrent sinus and ear infections, among other conditions. This is usually done as an outpatient procedure under general anesthesia.

Allergen: A substance that your body perceives as dangerous and causes an allergic reaction.

Allergic rhinitis: See Hay fever

Allergy: An exaggerated response to a substance or condition produced by the release of histamine or histamine-like substances in affected cells.

Allergy index: Measure of allergy sufferers who are affected by pollen in your region. Since some types of pollen may be more likely to cause allergies than others, a high allergy index does not necessarily correspond to a high pollen count.

Allergy shots: See Immunotherapy

Anaphylaxis: Severe, life-threatening allergic response that may include lowered blood pressure, swelling, and hives.

Angioedema: Swelling similar to urticaria (hives), but the swelling occurs beneath the skin instead of on the surface. Angioedema is characterized by deep swelling around the eyes and lips and sometimes of the hands and feet.

Antibodies: Specialized proteins produced by white blood cells that circulate in the blood. Antibodies seek and attach to foreign proteins, microorganisms, or toxins in order to neutralize them. They are part of the immune system.

Antigen: A substance, usually a protein, which the body perceives as foreign.

Antihistamine: Medication that prevents symptoms of congestion, sneezing and itchy, runny nose by blocking histamine receptors.

Anti-inflammatory: Type of medication that reduces swelling and inflammation.

Asthma: A disease of the branches of the windpipe (bronchial tubes) that carry air in and out of the lungs. Asthma causes the airways to narrow, the lining of the airways to swell, and the cells that line the airways to produce more mucus. These changes make breathing difficult and cause a feeling of not getting enough air into the lungs.

Bronchodilators: Medications used to relax the muscle bands that tighten around the airways during an asthma episode. Bronchodilators also help clear mucus from the lungs.

Conjunctivitis: Also called "pink eye." Conjunctivitis is an inflammation of the conjunctiva, the tissue that lines the inside of the eyelid.

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

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

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

Drug allergy: Allergic reaction to a specific medication. The most common cause of drug allergies is penicillin.

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 healthcare provider.

Food allergy: Allergy that occurs when the immune system responds defensively to a specific food protein that is not 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, rubber bands, etc.

Latex allergy: An allergy that develops after some sensitizing contact with latex.

Mast cell: A type of white cell that is involved in the 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 medications 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 Pollen and mold count

Myringotomy: Outpatient procedure in which small metal or plastic tubes are inserted through the eardrum to equalize pressure between the middle and outer ear.

Nasal endoscopy: A test that allows the doctor to view the nasal cavity to detect polyps or other abnormalities.

Nasal sprays: Medication used to prevent or treat nasal symptoms. Available by prescription or over-the-counter in decongestant, antihistamine, corticosteroid, or salt-water solution form. A mast cell (see above) stabilizer form is also available.

Otitis media: Bacterial or viral infection of the middle ear (the space behind the eardrum).

Otolaryngologist: A doctor who specializes in diagnosing and treating a variety of disorders of the ear, nose and throat.

Otoscope: A lighted instrument that lets the doctor see far down into the outer ear canal.

Pneumatic otoscope: An instrument that blows a puff of air into the ear canal to test eardrum movement.

Pollen: A fine, powdery substance released by plants and trees.

Pollen and mold counts: A measure of the amount of allergens in the air. The counts are usually reported for mold spores and three types of pollen: grasses, trees and weeds. The count is reported as grains per cubic meter of air and is translated into a corresponding level: absent, low, medium or high.

Pulmonary function test: A test that measures how well the lungs take in air and how well this air can be exhaled (lung function). Also measured is how efficiently the lungs transfer oxygen into the blood.

RAST (radioallergosorbent test): Blood test used to identify the substances that are causing your allergy symptoms and to estimate a relative sensitivity.

Sinusitis: Inflammation of the sinuses usually caused by bacterial infection. Acute sinusitis is the sudden onset of symptoms that can be treated with antibiotics and decongestants. Chronic sinusitis is characterized by multiple recurrences of sinusitis or infection that last s several weeks.

Tympanometry: A test in which sound and air pressure are used to check for disorders of the middle ear.

Urticaria (hives): Itchy, swollen, red bumps or patches on the skin that appear suddenly as a result of the body's adverse reaction to certain allergens. They can appear anywhere on the body including the face, lips, tongue, throat, or ears. Hives vary in size and can last for minutes or days.