Pulmonary Function Tests
by Editorial Staff and Contributors
Pulmonary function tests (PFTs) are a group of breathing tests. They can show how well your lungs are working. PFTs may measure:
Reasons for Test TOP
PFTs may be used to diagnose lung conditions or diseases, such as:
These tests may also be done to:
Possible Complications TOP
There are no major complications associated with this procedure.
What to Expect TOP
Prior to Test
Description of Test
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:
After Test TOP
Rest until you feel able to leave. You may be given medication if testing has caused wheezing, coughing, and/or difficulty breathing.
How Long Will It Take? TOP
Will It Hurt? TOP
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, or previous test results. Your doctor will discuss the results with you and decide if further testing or treatment is needed.
Call Your Doctor TOP
After the test, call your doctor if any of the following occurs:
American Lung Association
Family Doctor—American Academy of Family Physicians
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Pulmonary function tests (PFTs). Duke University Health System. DukeHealth.org website. Available at:
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Accessed September 26, 2014.
Barreiro TJ, Perillo I, et al. An approach to interpreting spirometry. Am Fam Physician. 2004;69(5):1107-1115.
Last reviewed August 2014 by Michael Woods, MD
Last Updated: 9/30/2013