Aerosolized beta 2-agonists do not induce bronchial hyperreactivity in healthy adults.

ABSTRACT

OBJECTIVE: To determine whether regular administration of beta 2-agonists could induce bronchial hyperreactivity in nonasthmatic volunteers. DESIGN: A prospective, randomized, double-blind, placebo-controlled, crossover clinical trial of 2 weeks therapy with a 2-week washout period between each treatment period. Treatments were albuterol or matching placebo as 2 inhalations 4 times daily. SUBJECTS: Ten healthy, nonsmoking women 27-37 years old. SETTING: General clinical research center of a tertiary care university hospital. MAIN OUTCOME MEASURES: Baseline spirometry and methacholine bronchoprovocation studies were performed immediately prior to, 12 hours following, and 1 and 2 weeks following each treatment period. RESULTS: No change was detected in either baseline spirometry or methacholine responsiveness. CONCLUSIONS: This suggests that if beta 2-agonists induce a rebound bronchial hyperreactivity, it is not the result of the production of tolerance or a direct effect on bronchial smooth muscle.