Pulmonary function tests (PFTs) are a group of breathing tests. They can show how well your lungs are working. PFTs may measure:
PFTs may be used to diagnose lung conditions or diseases, such as:
These tests may also be done to:
Most tests will require you to breathe into a mouthpiece. The mouthpiece may be attached to a simple handheld device or be part of a larger machine. Examples of devices are a spirometer or peak flow meter. You may be asked to breathe in and out in different patterns and speeds. You will rest between tests.
Tell the technician right away if you have breathing problems, pain, or dizziness during testing.
Other tests that may be used in some situations include:
Rest until you feel able to leave. You may be given medicine if testing has caused wheezing, coughing, and/or difficulty breathing.
The test does not hurt. You may feel symptoms of your lung condition during or immediately following testing.
Your doctor will compare the results of your tests with normal values based on your age, sex, and height. Your doctor will discuss the results with you and decide if further testing or treatment is needed.
After the test, call your doctor if any of the following occurs:
American Lung Association
Canadian Lung Association
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Last reviewed October 2012 by Brian Randall, MD
Last Updated: 10/11/2012