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Asthma Glossary of Terms



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.


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.

Monitoring: keeping track of.

Mucus: a material produced by glands in the airways, nose, and sinuses. Mucus cleans and protects certain parts of the body such as the lungs.

Nasal spray: medication used to help prevent and treat nasal congestion or nasal allergy symptoms. Available by prescription or over-the-counter in decongestant, corticosteroid, or salt-water solution form.

Nebulizer: a machine that changes liquid medicine into fine droplets (in aerosol or mist form) that are inhaled through a mouthpiece or mask. Nebulizers can be used to deliver bronchodilator (airway-opening) drugs such as albuterol and Atrovent, as well as anti-inflammatory or steroid medicines (Pulmicort Respules). A nebulizer may be used instead of a metered dose inhaler (MDI). It is powered by a compressed air machine and plugs into an electrical outlet.

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