What is Asthma?

Asthma is an inflammatory disease of the lungs that often makes breathing difficult and causes attacks of coughing, wheezing, tightness in the chest, and shortness of breath. Asthma symptoms occur when the lining of the air passages swell and the muscles surrounding the airways tighten. Mucus fills the airways, further reducing the amount of air that can pass through them and causing an asthma attack.