A type of disease that affects the lungs and other parts of the respiratory system. Pulmonary diseases may be caused by infection, by smoking tobacco, or by breathing in secondhand tobacco smoke, radon, asbestos, or other forms of air pollution. If you have COPD and you smoke, this is the most important thing you can do. inhalers and tablets – to help make breathing easier. pulmonary rehabilitation – a specialised programme of exercise and education. Over time, exposure to irritants that damage your lungs and airways can cause chronic obstructive pulmonary disease (COPD), which includes chronic bronchitis and emphysema. The main cause of COPD is smoking, but nonsmokers can get COPD too.