Methacholine Challenge

The Methacholine Challenge is a medical test used to diagnose airway abnormalities in patients with respiratory disorders such as asthma, chronic obstructive pulmonary disease (COPD), and bronchitis. During the test, the patient inhales a mist of the drug methacholine, a bronchoprovocative agent, which stimulates the airways of the lungs. This is done to measure the narrowing of the airways (airway hyperreactivity) in the lungs. If the airways become constricted more than expected, it can indicate airway abnormalities. The Methacholine Challenge test can help identify the underlying cause of the patient’s respiratory symptoms and can be an important tool in helping to formulate an effective treatment plan.