Spirometry is a lung function test. It measures the amount of air you breathe out (exhale). It also measures how quickly you can fully exhale. It may be used to diagnose many lung conditions.
Spirometry is advised for people with asthma. The results of this test help your doctor make a diagnosis. It is also used to keep track of asthma and to see how well medicines are working.
During this test you will sit upright with a clip on your nose. You will breathe out as hard and fast as you can through your mouth into a tube connected to a machine. In some cases. you will be given a medicine and will then repeat the test to see if there are changes. The test doesn't hurt.