Cough

A reflex action that occurs as an attempt to clear the airways of mucus, sputum, a foreign body, or any other irritants or blockages. A cough is productive when it brings up mucus or sputum and unproductive, or dry, when it does not. Many coughs are due to irritation of the airways by dust, smoke (see cough, smoker’s), or a viral infection of the upper respiratory tract (see cold, common; laryngitis; pharyngitis; tracheitis). Coughing is a feature of bronchitis, asthma, pneumonia, and lung cancer. Over-the-counter cough remedies are available; but, in general, they just ease symptoms. More specific treatment is directed at the underlying disorder.