[Skip to Content]
[Skip to Content Landing]
January 15, 1982

Methacholine Challenge

JAMA. 1982;247(3):305. doi:10.1001/jama.1982.03320280027017

This article is only available in the PDF format. Download the PDF to view the article, as well as its associated figures and tables.


To the Editor.—  This letter is in regard to the article by Myers et al (1981;246:225).The mecholyl challenge has been with us for at least 30 years. In fact, the term "twitchy lung" is common in the allergy literature and was coined to describe the condition of patients whose bronchospasm is readily accentuated by challenge with methacholine.Such challenge does provide some indication of the underlying condition, but it does so while increasing the severity of that condition. It would be preferable to use a diagnostic technique involving exposure to a bronchodilating substance such as epinephrine that will improve the parameters of lung function and the clinical condition while helping to elucidate the cause. An improvement of 10% in lung function after bronchodilation is generally considered to be normal; more than 20% improvement indicates that there was preexisting bronchospasm.Why would anyone prefer a test that might worsen the