What Is Asthma?

Asthma is a lung disease that results in blockage of the airways. During an asthma attack, the muscles around the bronchi (the small passageways of the lungs) tighten and narrow, making it difficult for air to leave the lungs.

The chronic inflammation and excessive sensitivity of the bronchi produce those constricting spasms. The bronchial tubes swell and become plugged with mucus. An attack, often occurring at night, usually begins as a nonproductive cough and wheezing; this is often followed by difficult breathing and a tight chest. After a few hours, it subsides.

Symptoms include difficult breathing, coughing, wheezing, tight chest. Attacks or multiply symptoms can occur suddenly or gradually. Sometimes there is coughing with thick, persistent sputum that may be clear or yellow. There is a feeling of suffocation. Children often have coughing and vomiting episodes.