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Cough lasting 3-8 weeks (Sub-Acute)

A cough that lasts for 3-8 weeks is often caused by a cold or other lung infection that lasts longer than normal. A cough that lasts 3-8 weeks may go away by itself but it may also need treatment. If you have a three-week cough and you are not sure if you should see your doctor, read the following questions:

  • Are you coughing up blood?
  • Are you short of breath?
  • Has your cough has changed over time?
  • Are you losing weight without trying?
  • Are you coughing up phlegm?
  • Do you have a fever?
  • Do you currently smoke?
  • Did you smoke in the past?
  • Are you living with asthma or COPD or other respiratory conditions?

If you answered yes, to any of these questions, you should talk to your doctor about your cough.

To diagnose your cough your doctor may ask you questions about your family history, things you may have been exposed to at home or work, and if you smoked. Your doctor may want to examine you. Your doctor may also give you a few tests including:

  • A chest X-ray to take a picture of your lungs. This can tell your doctor if you have something like pneumonia or lung cancer.
  • Spirometry - This test measures how much air you can breathe out and in. Your doctor will use spirometry to diagnose conditions such as asthma or COPD.