Short- versus long-acting angiotensin converting enzyme (ACE) inhibitors: Although ACE inhibitors are widely used in the treatment of hypertension, there are few data on trough: peak ratios and the data are contradictory. Part of the explanation for this lies in differences in pharmacological properties. Depending on the kinetics of elimination, the trough: peak ratio of short- and long-acting ACE inhibitors has to be evaluated according to a dose regimen of twice or once a day, respectively, and must take account of the dose used, since long-acting ACE inhibitors appear to have a dose-dependent trough: peak effect. Further explanations for the contradictory trough: peak ratios reported for ACE inhibitors include measurement methods (clinic blood pressure versus ambulatory monitoring) and study design.
Trough: peak ratio: Data from randomly allocated, placebo-controlled studies indicate that both the short-acting ACE inhibitors captopril and quinapril given twice a day and the long-acting ACE inhibitors enalapril, lisinopril, benazepril and cilazapril given once a day have an acceptable trough: peak ratio (>50%). The evidence suggests that when chemically different ACE inhibitors with similar kinetics of elimination are administered at equipotent doses, similar trough: peak ratios are obtained.