Amelioration of Enalapril-Induced Dry Cough by Changing Dosing Time from Morning to Evening; A Preliminary Trial.

Objective: To determine whether the severity and frequency of dry cough induced by enalapril, an angiotensin-converting enzyme (ACE) inhibitor, might be altered by changing its administration time.Methods: Twenty-one patients with hypertension and three with chronic heart failure received enalapril (5 mg) once daily in the morning for more than 2 weeks and complained of persistent, non-productive dry cough. After the severity and frequency of cough were evaluated using a questionnaire, enalapril (5 mg) was given once daily in the evening for more than 2 weeks. At the end of this period, patients were asked to specify any changes in their cough during the evening treatment regimen, according to the following 5-point response scale: 1 (much worse), 2 (moderately worse), 3 (no change), 4 (moderately improved) and 5 (much improved).Results: The severity of dry cough was attenuated [mean change (and 95% CI): 3.75 (3.37-4.13)] and the frequency was reduced [mean change: 3.79 (3.44-4.14)] after the administraiton time was changed to evening.Conclusion: Dry cough is the most common adverse effect of ACE inhibitors. The present findings suggest that a chronopharmacological approach might ameliorate enalapril-induced dry cough and, consequently, improve QOL in treated patients.