How does a doctor test for asthma?

Your doctor will ask questions about your medical history, examine you, and run tests to see how well your lungs work. These are called lung function tests. They are easy and painless, requiring you simply to breathe into an instrument. One such instrument is called a spirometer.

Another test your doctor may give you is a Methacholine challenge test. Your doctor will have you breathe in a drug called methacholine. If you have a reaction to it, then you probably have asthma.

Your doctor may also order a chest X-ray or a sinus X-ray and he may want you to be tested for allergies.

Doctors often ask the patient, or a caregiver, to keep a daily diary. The diary records symptoms, times when you had to restrict your actions, what medicine you took and when. A diary is a useful tool in understanding the causes, effects and medications for asthma.

To learn more:

Asthma: Steps in diagnosis
The Mayo Clinic's health information site explains how asthma is diagnosed and what kind of tests are used.
(Mayo Clinic)
Provides a description of spirometry, a lung function test used to diagnose asthma and other lung diseases.

next » Questions to ask your doctor about asthma.

Written by: Lillian Trettin, Ph.D.
Reviewed by: Jeffrey G. Schultze, M.D.
Last Modified: Tuesday November 24, 2009 10:19 AM