Cryptogenic organising pneumonia (COP)

COP is a swelling of the small airways in your lung. It is also sometimes called bronchiolitis obliterans organising pneumonia or BOOP.

It has symptoms that can closely mimic a pneumonia infection, such as fever, tiredness, coughing and breathlessness.

Because this condition is rare, it may take some time to get a diagnosis. Your doctor will need to consider other possible causes of your symptoms. You may need to have a few tests and you might need to see a specialist.

COP is usually treated with corticosteroids or antibiotics, and treatment is usually successful.

Useful resources:

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Last medically reviewed: December 2016. Due for review: December 2019

This information uses the best available medical evidence and was produced with the support of people living with lung conditions. Find out how we produce our information. If you’d like to see our references get in touch.