Some prescribed medicines can also cause a cough (for example, ACE-inhibitors, which are medicines for treating heart failure). Rarely, a cough is a symptom of a more serious condition such as lung cancer, heart failure, a pulmonary embolism (clot on the lung), tuberculosis (TB) or pneumonia.
Coughs caused by the common cold or by flu usually clear up after a few days. However, a cough that's caused by a lung infection, such as bronchitis, may be present for several weeks after the infection has gone because the inflammation in the airways can take a while to clear. If you've had a cough for more than two weeks following a viral infection, seek medical advice from your GP.
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