What is Bronchodilator Reversibility Testing?
After a baseline spirometry, you inhale a bronchodilator medicine (such as salbutamol) and spirometry is repeated after about 15 minutes. A significant improvement supports a diagnosis of asthma; it also helps characterise COPD.
Why it is done
- Distinguishing asthma from COPD
- Assessing response to bronchodilators
Before the procedure
- Avoid smoking for at least 24 hours (ideally longer) before the test
- Avoid heavy meals and vigorous exercise shortly before the test
- Wear loose, comfortable clothing
- You may be asked to withhold certain inhalers before the test — follow the instructions you are given
During the procedure
- Baseline spirometry
- Inhalation of a bronchodilator via a spacer
- Repeat spirometry after 10–15 minutes
After the procedure
- Some people feel a mild tremor or palpitations for a short time from the bronchodilator
Safety & risks
Breathing tests are non-invasive and very safe. Some people feel briefly light-headed or tired from the breathing efforts. Tests may be postponed after a recent heart attack, eye or chest surgery, or if you are unwell.
Preparation instructions may differ for individual patients — please follow the specific advice given at your consultation.