The blood pressure effect of 8-day angiotensin converting enzyme (ACE) inhibition was studied in normotensive healthy volunteers maintained on an unrestricted salt intake. Six volunteers received cilazapril (5 mg/day), 5 perindopril (8 mg/day) and 5 CGS14824A (10 mg/day). The 3 investigational inhibitors were found to have no consistent effect on blood pressure monitored during day-time outside the clinic using a semi-automatic blood pressure recorder (Remler M2000).