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Asthma Glossary of Terms


Contraindication: a reason not to use a course of treatment or medication.

Dander, animal: tiny scales shed from animal skin or hair. Dander floats in the air, settles on surfaces and is a major part of household dust. Cat 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.

Dehydration: excessive loss of water.

Diaphragm: the major muscle of breathing, located at the base of the lungs.

Dry powder inhaler (DPI): a device for inhaling respiratory medications that come in powder form.

Dust mites: a common trigger for allergies.

Dyspnea: shortness of breath.

Exacerbation: worsening.

Exercise induced asthma: asthma that is made worse when exercising

Exhalation: breathing air out of the lungs

(HEPA) high-efficiency particulate air filter: a filter that 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. When you inhale an allergen, mast cells located in the nose and lungs release histamine. Histamine then attaches to receptors on nearby blood vessels, causing them to enlarge (dilate). Histamine also binds to other receptors located in nasal tissues, causing redness, swelling, itching, and changes in the secretions.

Holding chamber: see spacer.

Humidification: the act of moisturizing the air with molecules of water.

Hyperventilation: excessive rate and depth of breathing.

Immune system: the body's defense system that protects us against infections and foreign substances.

Indication: reason to use.

Inflammation: a response in the body includes swelling and redness.

Inhaler: See metered dose inhaler (MDI).

Inhalation: breathing air into the lungs.

Irritants: things that bother the nose, throat, or airways when they are inhaled (not an allergen).

Leukotriene modifier: drug that blocks chemicals called leukotrienes in the airways. Leukotrienes occur naturally in the body and cause tightening of airway muscles and production of excess mucus and fluid. Leukotriene modifiers work by blocking leukotrienes and decreasing these reactions. These medications may also be helpful in improving airflow and reducing some symptoms of chronic obstructive pulmonary disease (COPD).

Medical history: a list of a person's previous illnesses, present conditions, symptoms, medications, and health risk factors.

Metered dose inhaler (MDI): small aerosol canister in a plastic container that releases a mist of medication when pressed down from the top. This drug can be breathed into the airways. Many asthma medications are taken using an MDI.

Mold: parasitic, microscopic fungi (like Penicillin) with spores that float in the air like pollen. Mold is a common trigger for allergies and can be found in damp areas, such as the basement or bathroom, as well as in the outdoor environment in grass, leaf piles, hay, mulch, or under mushrooms.

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