Bronchial provocation (challenge) testing is the most commonly used and accepted approach for evaluating airway hyperresponsiveness (twitchy airways). Bronchial challenge testing utilizes methacholine to assess airway hyperresponsiveness. The most commonly used nonspecific challenge agent is aerosolized methacholine. In this test, the patient inhales an aerosol of one or more concentrations of methacholine. Results of pulmonary function tests (e.g., spirometry and specific conductance) performed before and after the inhalations are used to measure the response. Your healthcare provider will provide you with a list of medications thatbe withheld on the day of the test, whichaffect the methacholine challenge test. Performing the test: · This is a timed test. You will be asked to inhale an aerosol concentration for 2 minutes. · You will then do the pulmonary function test. · You will continue repeating this procedure until the test is completed. · If required you will be given a bronchodilator treatment at the end of the test Pulmonary Function Laboratory: Methacholine Challenge