Chronic obstructive pulmonary disease (COPD)
Chronic obstructive pulmonary disease, or COPD, is characterized by abnormalities in the lungs that make it difficult to exhale normally. Generally, two distinct diseases are involved: emphysema and chronic bronchitis. Emphysema and chronic bronchitis cause excessive inflammatory processes that eventually lead to abnormalities in lung structure that permanently obstruct airflow (hence the term \"chronic obstructive\"). Symptoms include shortness of breath (dyspnea), wheezing, chronic cough, barrel chest, and pursed-lip breathing (see Symptoms). Asthma is usually reversible, but some asthmatics have permanently narrowed airways and suffer COPD.
