The Pulmonary Function Test is a specialized lung test. A series of breathing maneuvers and measurements help your physician assess the function of your lungs, diagnose pulmonary abnormalities, and assess the response of your lungs to medications. The entire procedure takes about an hour.

Avoid the following for four hours before the test:

1. Smoking.
2. Heavy meals, carbonated beverages, and caffeine.
3. Bronchodialators (inhalers/breathing treatments/nebulizers).