What is a chronic cough?

Coughing is good because it helps to clear foreign objects and mucus from your lungs and breathing tubes. However, a cough that lasts a long time can be the sign of a health problem. A chronic cough is a cough that lasts longer than eight weeks.

What can cause a chronic cough?

There are many possible causes. Here are some common causes of chronic cough:

• Smoking and lung damage from smoking

• Angiotensin-converting enzyme (ACE) inhibitors (medicines used to treat high blood pressure and heart failure)

• Allergies

• Asthma

• Sinus problems

• Acid reflux from the stomach (also called heartburn)

Rare causes of chronic cough include tuberculosis and lung cancer.

How will my doctor find the cause of my chronic cough?

Your doctor will ask you if you smoke now, or if you smoked in the past. You also will be asked about any medicines that you take. Your doctor will ask if you are exposed to chemicals where you work, or if you have allergies.

If you are a smoker, your doctor will ask you to stop smoking. If you are taking an ACE inhibitor, your doctor will change you to a medicine that does not cause cough. If you are exposed to chemicals or other irritants, your doctor will ask you to take measures to avoid this exposure.

If your cough is not caused by smoking, a medicine, or a chemical or other irritant, your doctor may order some tests.

What tests might I need?

A chest x-ray is usually the first step.

If your chest x-ray is normal, your doctor will look for common conditions that can cause chronic cough, like postnasal drip, acid reflux disease, and asthma. Your doctor may prescribe medicine or lifestyle changes to treat these problems and stop your cough.

If your x-ray is not normal, you may need to have a lung scan or lung function tests. Depending on what these tests show, your doctor might have you see a pulmonologist (a doctor with special training in lung and breathing problems).

If you have a disease that affects your immune system, such as HIV infection, your doctor may order other tests.

What if my child has a chronic cough?

Chronic cough usually has the same causes in children as in adults. Sometimes, however, young children can have a cough because an object is stuck in their windpipe. Tests may be needed to look for the object.

Talk to your doctor if your child has a chronic cough.