Pulmonary function tests (PFTs) are a group of tests that measure how well your lungs work. This includes how well you’re able to breathe and how effective your lungs are able to bring oxygen to the rest of your body.

Your doctor may order these tests:

• if you’re having symptoms of lung problems
• as part of a routine physical
• to monitor how effective your treatment is if you have a lung disease, such as asthma
• to assess how well your lungs are working before you have surgery

PFTs are also known as spirometry or lung function tests.

PFTs can help diagnose:

• asthma
• allergies
• chronic bronchitis
• respiratory infections
• lung fibrosis
• bronchiectasis, which is a condition in which the airways in the lungs stretch and widen
• chronic obstructive pulmonary disease (COPD), which used to be called “emphysema”
• asbestosis, which is a condition caused by exposure to asbestos
• sarcoidosis, which is an inflammation of your lungs, liver, lymph nodes, eyes, skin, or other tissues
• scleroderma, which is a disease that affects your connective tissue
• pulmonary tumor
• lung cancer