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Asthma



	Asthma is a disease in which inflammation of the airways causes airflow into and out of the lungs to be restricted. The muscles of the bronchial tree become tight and the lining of the air passages swells, reducing airflow and producing the characteristic wheezing sound. This is known as an asthma attack, which can occur as an allergic reaction to an allergen or other substance (acute asthma), or as a part of a complex disease cycle which may include reaction to stress or exercise (chronic asthma).

Update Date: 5/21/2009

Updated by: Allen J. Blaivas, DO, Division of Pulmonary and Critical Care, UMDNJ-New Jersey Medical School, Newark, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

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