Bronchitis is an inflammation of the air passages in the lungs. The condition occurs over a long period and recurs over several years. Symptoms include excessive bronchial mucus with a cough producing sputum. Cigarette smoking (active and passive exposure) is the chief cause of this disease, with air pollution, infection, familial factors, and allergies as exacerbating factors.
Review Date 11/14/2016
Updated by: Denis Hadjiliadis, MD, MHS, Paul F. Harron Jr. Associate Professor of Medicine, Pulmonary, Allergy, and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.