Asthma (from the Greek ἅσθμα, ásthma, "panting") is a common chronic inflammatory disease of the airways characterized by variable and recurring symptoms, reversible airflow obstruction and bronchospasm.[2] Common symptoms include wheezing, coughing, chest tightness, and shortness of breath.[3]
Asthma is thought to be caused by a combination of genetic and environmental factors.[4] Its diagnosis is usually based on the pattern of symptoms, response to therapy over time and spirometry.[5] It is clinically classified according to the frequency of symptoms, forced expiratory volume in one second (FEV1), and peak expiratory flow rate.