A chronic cough is a cough that lasts eight weeks or longer in adults, or four weeks in children.
Common causes include:
- Asthma. An asthma-related cough may come and go with the seasons, appear after an upper respiratory tract infection, or become worse when you're exposed to cold air or certain chemicals or fragrances.
- Blood pressure drugs. Angiotensin-converting enzyme (ACE) inhibitors, which are commonly prescribed for high blood pressure and heart failure, are known to cause chronic cough in some people.
- Chronic bronchitis. This long-standing inflammation of your major airways can cause a cough that brings up colored sputum.
- Gastroesophageal reflux disease. Stomach acid flows back into the tube that connects your stomach and throat. The constant irritation can lead to chronic coughing.
- Infections. A cough can linger long after other symptoms of pneumonia, flu, a cold or other infection of the upper respiratory tract have gone away.
- Postnasal drip. When your nose or sinuses produce extra mucus, it can drip down the back of your throat and trigger your cough reflex.