Asthma, from the Greek Άσθμα (ásthma)[cn], meaning gasp, is a common chronicinflammatory disease of the airways characterized by variable and recurring symptoms, reversible airflow obstruction, and bronchospasm. Symptoms include wheezing, coughing, chest tightness, and shortness of breath.

Treatment of acute symptoms is usually with an inhaled short-acting beta-2 agonist (such assalbutamol). Symptoms can be prevented by avoiding triggers, such as allergens and irritants, and by inhaling corticosteroids. Leukotriene antagonists are less effective thancorticosteroids and thus less preferred.

The prevalence of asthma has increased significantly since the 1970s. As of 2009, 300 million people were affected worldwide. In 2009 asthma caused 250,000 deaths, although generally with treatment, prognosis is good.