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Asthma - Overview

Alternative Names

Bronchial asthma; Exercise-induced asthma

Definition of Asthma:

Asthma is a disorder that causes the airways of the lungs to swell and narrow, leading to wheezing, shortness of breath, chest tightness, and coughing.

Causes, incidence, and risk factors:

Asthma is caused by inflammation in the airways. When an asthma attack occurs, the muscles surrounding the airways become tight and the lining of the air passages swells. This reduces the amount of air that can pass by.

In sensitive people, asthma symptoms can be triggered by breathing in allergy-causing substances (called allergens or triggers).

Common asthma triggers include:

Animals (pet hair or dander)
Dust
Changes in weather (most often cold weather)
Chemicals in the air or in food
Exercise
Mold
Pollen
Respiratory infections, such as the common cold
Strong emotions (stress)
Tobacco smoke

Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) provoke asthma in some patients.

Many people with asthma have a personal or family history of allergies, such as hay fever (allergic rhinitis) or eczema. Others have no history of allergies.

Reviewed last on: 5/1/2011
David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc., and Denis Hadjiliadis, MD, Assistant Professor of Medicine, Division of Pulmonary, Allergy and Critical Care, University of Pennsylvania, Philadelphia, PA.

References

Lugogo N, Que LG, Fertel D, Kraft M. Asthma. In: Mason RJ, Broaddus VC, Martin TR, et al. Murray & Nadel's Textbook of Respiratory Medicine. 5th ed. Philadelphia, Pa: Saunders Elsevier; 2010:chap 38.

Brozek JL, Bousquet J, Baena-Cagnani CE, Bonini S, Canonica GW, Casale TB, et al. Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines: 2010 revision. J Allergy Clin Immunol. 2010 Sep;126(3):466-76.

National Asthma Education and Prevention Program Expert Panel Report 3: Guidelines for the Diagnosis and Management of Asthma. Rockville, MD. National Heart, Lung, and Blood Institute, US Dept of Health and Human Services; 2007. NIH publication 08-4051.

Wechsler ME. Managing asthma in primary care: putting new guideline recommendations into context. Mayo Clin Proc. 2009;84:707-717.

Fanta CH. Asthma. N Engl J Med. 2009;360:1002-1014.

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