- No smoking or heavy exercise 4-6 hours before the test
- Avoid taking certain medications that can affect lung function (check with your doctor)

- You’ll breathe into a device called a spirometer, which measures the amount and speed of air you can inhale and exhale
- The test involves a series of deep breaths, forceful exhalations, and sometimes holding your breath

- The test is generally non-invasive and safe, but you might feel slightly lightheaded or winded after forceful breathing
- It’s usually not painful, but it may feel a little tiring

- You can resume your normal activities right away
- Your doctor will review the results and discuss any necessary next steps