Chronic obstructive pulmonary disease (COPD) slowly damages the lungs and affects how you breathe.
In COPD, the airways of the lungs (bronchial tubes) become inflamed and narrowed. They tend to collapse when you breathe out and can become clogged with mucus. This reduces airflow through the bronchial tubes, a condition called airway obstruction, making it difficult to move air in and out of the lungs.
The inflammation of the bronchial tubes makes the nerves in the lungs very sensitive. In response to irritation, the body forces air through the airways by a rapid and strong contraction of the muscles of respiration-a cough. The rapid movement of air in the breathing tubes helps remove mucus from the lungs into the throat. People with COPD often cough a great deal in the morning after a large amount of mucus has built up overnight (smoker’s cough).