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URL of this page: //medlineplus.gov/ency/imagepages/19321.htm
Asthma
Overview
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).
Review Date 1/1/2025
Updated by: Frank D. Brodkey, MD, FCCM, Associate Professor, Section of Pulmonary and Critical Care Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.