A methacholine challenge is a breathing test to see if you may have asthma. You will breathe in a mist that has a medicine called methacholine in it. You will breathe in higher doses, with tests done after each dose. This medicine tests the airways for reactivity or tightening. The test will take 30 to 90 minutes.

How to Prepare

  • Do not exercise or eat a heavy meal for at least four hours before the test.

  • Do not have any caffeine, coffee, tea, cola or chocolate.

  • Do not smoke on the day of the test.

  • Tell your doctor if you are pregnant. This test will not be done if pregnant or nursing.

If you have or had a recent cold, flu or other illness, this test will need to be scheduled two weeks after the end of your illness.


You may keep using inhaled corticosteroids, but you will need to stop other medicines before this test. Before the test, please stop:

  • Albuterol: 6 hours before test

  • Atrovent, Combivent: 24 hours before test

  • Theophylline: 24 hours before test

  • Advair®, Wixela, Symbicort®, Dulera® 36 hours before test

  • Breo Ellipta®: 48 hours before test

  • Spiriva®, Incruse Ellipta®, Anoro Ellipta®, Trelegy®: 1 week before test

During the Test

You may have mild shortness of breath, cough or chest tightness. If you do, you may be given some medicine from an inhaler.

After the Test

You will be able to eat, drink, and keep your normal routine after the test. Your doctor will discuss your test results with you.

When to Call

Call if you have any questions or concerns before the test.

Who to Call

Pulmonary Function Lab

Monday-Friday, 8:00 am to 4:30 pm

(608) 263-7000

The toll-free number is 1-800-323-8942. Ask for the Pulmonary Function Lab.