An examination of food hypersensitivity as a cause of increased bronchial responsiveness to inhaled methacholine.

To determine if food challenges could alter bronchial hyperresponsiveness, methacholine challenges were performed before and 24 hours after double-blind, placebo-controlled food challenges on 11 subjects with asthma with a history of food-induced asthma and positive skin prick tests to the suspect food. An equal number of patients demonstrated increased methacholine sensitivity after food and placebo challenges. Thus, we could not find evidence that allergic reactions to food induced bronchial hyperresponsiveness.