1. Chronic obstructive pulmonary disease  (Trust Mark: Doctor-Reviewed)
Chronic obstructive pulmonary disease (COPD) is lung disease that makes it difficult to breathe. There are two main forms of COPD: Chronic bronchitis, which causes long-term swelling and a large amount of mucus in the main airways in the lungs; Em...• Reviewer: Benjamin Medoff, MD, Assistant Professor of Medicine, Harvard Medical School, Pulmonary and Critical Care Unit, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

2. Chronic Obstructive Lung Disease  (Trust Mark: Doctor-Reviewed)
Chronic obstructive lung disease, also known as chronic obstructive pulmonary disease (COPD), is a general term for a group of conditions in which there is persistent difficulty in expelling (or exhaling) air from the lungs. COPD commonly refers t...• Author: Harry W. Golden