have cough that won't go away?
['An infection. If your cough did accompany a cold, pneumonia, or the flu, keep in mind that it can linger for a while after the infection has cleared. ... ', 'Chronic obstructive pulmonary disease (COPD). ... ', 'Asthma. ... ', 'Postnasal drip. ... ', 'Cystic fibrosis. ... ', 'Gastroesophageal reflux disease (GERD).']