What are pulmonary function tests?

These tests answer the question, “How well are you breathing?”

Pulmonary function tests, also referred to as lung function tests, measure how well your lungs inhale and exhale air. Depending on the tests used, they may measure how well your lungs transfer oxygen to the blood.

Why do you need pulmonary function tests?

Pulmonary function testing can help you and your doctor:

  • Detect narrowing in the airways of your lungs
  • Identify early changes in your lungs’ ability to transfer oxygen to your blood
  • Decide if a medicine, such as a bronchodilator, could be helpful
  • Show whether exposure to substances in your environment has harmed your lungs
  • Determine your ability to tolerate surgery and medical procedures
  • Measure the effect of chronic diseases like asthma, chronic obstructive pulmonary disease (COPD), or cystic fibrosis on lung function in order to better determine the course of treatment

What symptoms would make a doctor recommend pulmonary function tests?

If you have:

  • Shortness of breath
  • Coughing
  • Coughing up mucus or phlegm
  • Wheezing
  • Difficulty breathing
  • Fatigue
  • History of smoking

Then you may be at risk for:

Last reviewed by a Cleveland Clinic medical professional on 09/27/2018.


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