Bronchial Challenge Tests

Also known as: bronchial provocation tests, methacholine challenge test.

What are bronchial challenge tests?

A bronchial challenge test is a tool used by physicians to diagnose asthma and other breathing problems. It involves using chemicals or allergens in a controlled environment to simulate the symptoms of asthma, and then diagnose the results.

What happens during the procedure?

The patient first does some basic breathing tests in order to establish lung function before the test. Then the patient inhales a chemical known as methacholine, or another allergy-causing substance, through a nebulizer machine. Afterward, the patient repeats the breathing tests, and the physician notes the changes in lung function.

Is any special preparation needed?

The patient may need to avoid smoking, certain medications, cold air and exercise before the test. The test may not be given if the patient has or has recently had a cold or other respiratory infection.