Effects of enalapril, an ACE-inhibitor, on bronchial responsiveness in asthmatics.

To assess the effects of enalapril on bronchial responsiveness, we studied ten stable asthmatics and five healthy normal volunteers. Spirometry and methacholine bronchoprovocation dose (PC20) were measured before and after oral administration of 20 mg enalapril. Significant hypotensive effect was observed in all. More than two fold (2.73) increase in bronchial responsiveness was observed in the asthmatics (P < 0.01) without significant change in the expiratory flows. PC20 after enalapril fell by 56.8 +/- 23.0% of baseline value (P < 0.001). No significant change was observed in spirometric parameters and bronchial responsiveness in normal subjects. We conclude that enalapril significantly enhances BR and cannot be used safely in treatment of hypertension in asthmatics.