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Asthma Glossary of Terms

Allergen: a substance (such as a food or pollen) that your body perceives as dangerous and can cause an allergic reaction.

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

Recommended Related to Asthma

Bronchodilators and Asthma

A bronchodilator is used by almost all people with asthma as a way to open the airway passages. Short-acting bronchodilators are used as a "quick relief" or "rescue" medication, while long-acting bronchodilators are used every day to control asthma -- in conjunction with an inhaled steroid. 

Read the Bronchodilators and Asthma article > >

Alveoli: thin-walled, small sacs located at the ends of the smallest airways in the lungs where the exchange of oxygen and carbon dioxide takes place.

Antibiotic: medication used to treat infection caused by bacteria. Antibiotics do not protect against viruses and do not prevent the common cold.

Anticholinergics: (also called cholinergic blockers or "maintenance" bronchodilators). This type of medicine relaxes the muscle bands that tighten around the airways. This action opens the airways, letting more air out of the lungs to improve breathing. Anticholinergics also help clear mucus from the lungs.

Antihistamine: medication that stops the action of histamine, which causes symptoms of allergy such as itching and swelling.

Anti-inflammatory: medication that reduces inflammation (swelling in the airway and mucus production).

Asthma: a disease of the airways or branches of the lung (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. Common symptoms include cough, shortness of breath, wheezing, chest tightness, and excess mucus production.

Bacteria: infectious organisms that may cause sinusitis, bronchitis, or pneumonia.

Beta2-agonists: a bronchodilator medication that opens the airways of the lung by relaxing the muscles around the airways that have tightened (bronchospasm). These medications may be short acting (quick relief) or long acting (control) medications. Short acting beta2 agonists are the drugs used to relieve asthma symptoms when they occur.

Breath sounds: lung sounds heard through a stethoscope.

Breathing rate: the number of breaths per minute.

Bronchial tubes: airways in the lung that branch from the trachea (windpipe).

Bronchioles: the smallest branches of the airways in the lungs. They connect to the alveoli (air sacs).

Bronchodilator: a drug that relaxes the muscle bands that tighten around the airways. Bronchodilators can also help clear mucus from the lungs.

Bronchospasm: the tightening of the muscle bands that surround the airways, causing the airways to narrow.

Carbon dioxide: a colorless, odorless gas that is formed in the tissues and is delivered to the lungs to be exhaled.

Chronic disease: a disease that can be controlled, but not cured.

Cilia: hair-like structures that line the airways in the lungs and help to clean out the airways.

Clinical trials: research programs conducted with patients to evaluate a new medical treatment, drug, or device. The purpose of clinical trials is to find new and improved methods of treating different diseases and special conditions.

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