Reviewed by Dr. Clement J. Cheng
Bronchitis is an inflammation of the bronchial passages, which are the main air passages to the lungs. Bronchitis is usually a secondary infection that follows a respiratory virus such as influenza or the common cold. Bronchitis is classified under the more general term chronic obstructive pulmonary disease. It is diagnosed specifically as having increased mucus and recurrent cough during a three month period for at least two consecutive years.