The Protective Effects of Ipratropium Bromide and Terbutaline on Distilled Water-induced Bronchoconstriction

Abstract Summary: In a randomized, double-blind, placebo-controlled study, we investigated the protective effects of ipratropium bromide 160 μg and 320 μg and terbutaline 500 μg on ultrasonically nebulized distilled water (UNDW)-induced bronchoconstriction in nine stable asthmatic patients. Both drugs caused a significant increase ( P 1 with no significant differences between the drugs or both doses of ipratropium bromide. Pre-inhalation of ipratropium bromide 320 μg and terbutaline 500 μg inhibited UNDW-induced bronchoconstriction ( P 1 and PD 20 UNDW, indicating that the protective effect on UNDW-induced bronchoconstriction is not dependent on the bronchodilation induced by terbutaline and ipratropium bromide. It also appears that the UNDW-induced bronchoconstriction is at least partly vagally mediated.