Bronchodilator reversibility testing is used to help your doctor assess your lung function after you have been given a type of lung medication called a bronchodilator. It's often used in people who have asthma or chronic obstructive pulmonary disease, or COPD.
This test uses spirometry and a bronchodilator. You are given the drug to relax your breathing muscles so that you can breathe more easily. The amount of improvement in your breathing after taking the bronchodilator can help your doctor diagnose lung problems or monitor the status of an existing lung condition.
Spirometry is performed with a machine to record how much air you can blow out per second and in total. You’ll be asked to breathe in deeply and then blow out as hard as you can into a tube. The tube connects to the machine’s computer.
You may need this test to learn your maximum lung function. In some cases, this test may be done to help your health care provider give you a more accurate prognosis or craft your treatment plan.
It’s important to follow instructions exactly when preparing for and during the test. For example, an accurate reading is tied closely to the timing of the drug dose and the spirometry. This will help your health care team get the most accurate information about how the medicine affects your breathing and how your lungs are working. If you are already taking lung medicine, you may be told not to take the medicine for a certain period of time before the test, depending on the reason your doctor wants the test done.