Comparative double-blind study of ramipril and captopril in mild to moderate essential hypertension

The angiotensin converting enzyme inhibitors ramipril and captopril were administered in doses of 10 mg once daily and 50 mg twice daily, respectively, to patients with mild to moderate essential hypertension. After a 4-week single-blind placebo washout period, patients were treated for 12 weeks with 1 of the drugs under double-blind conditions. Patients who did not respond after 6 weeks of treatment were given 50 mg hydrochlorothiazide concomitantly. The ramipril group showed greater decreases in blood pressure compared with baseline values: 20.1/14.9 mm Hg (ramipril) compared with 16.5/13.5 mm Hg (captopril). A further 6 weeks of treatment lowered the blood pressure even more: 22.5/20.0 mm Hg (ramipril) compared with 20.5/18.6 mm Hg (captopril). Concomitant hydrochlorothiazide given to nonresponders reduced the blood pressure levels in 24 of 40 patients in the ramipril group and in 20 of 36 patients in the captopril group. At the end of the study the overall response to treatment with ramipril alone and ramipril plus hydrochlorothiazide was 77.1%. The overall response rate in the captopril group was 82.7%. No clinically relevant adverse reaction occurred in any patient. Ramipril given once daily was as effective as captopril given twice daily in lowering blood pressure. Both drugs proved to be safe during treatment for 12 weeks.