Understanding Spirometry

To diagnose and check asthma, your doctor examines you. They listen to your lungs in your chest and ask you to breathe. You are asked questions about your symptoms, triggers, and any family history of asthma or allergies. Lung function tests may also be done. One of these is a spirometry test.

Spirometry is an easy test. It tells your doctor how well your lungs are working. The test generally takes 15 to 30 minutes. It can be done at a doctor's office or in a pulmonary function lab. Spirometry is rarely used for children younger than 6 years.

Your doctor will tell you any special directions before the test. They may tell you to stop taking certain medicines, not smoke, or not eat a large meal beforehand. Wear loose, comfortable clothing that allows you to take a big breath.

A trained technician will help with the test. You will sit upright. A nose clip will be placed on your nose so you only breathe through your mouth. You will put your mouth around a mouthpiece that is connected to the spirometer.

The spirometer measures the amount of air you breathe out (exhale). It also measures how quickly you can exhale completely.

Spirometry is a recommended test for people with asthma. It can help with the following: