Low-dose captopril for the treatment of mild to moderate hypertension. I. Results of a 14-week trial

We randomized 495 men with uncomplicated hypertension (diastolic BP, 92 to 109 mm Hg) to one of five captopril regimens at the following dosages: 12.5 mg three times a day, 25 mg three times a day, 37.5 mg twice daily, 50 mg three times a day, or placebo three times a day. After seven weeks, BP reduction with each captopril dose was greater than in the placebo group, averaging 10.2 to 14.2/8.6 to 10.5 mm Hg. Captopril, 37.5 mg/day, was as effective as 150 mg/day. Hydrochlorothiazide, 25 mg twice daily, was added for seven more weeks to all patients receiving placbo and to two thirds of those randomized to captopril therapy. Blood pressure reduction averaged 12.0/8.7 mm Hg in those receiving hydrochlorothiazide alone and 24.9 to 26.4/14.4 to 17.3 mm Hg in those receiving a combination of hydrochlorothiazide and captopril. Added hydrochlorothiazide greatly enhanced the antihypertensive response. The 15 terminations (4.3%) related to captopril were not life threatening. Conclusion: Captopril treatment of uncomplicated hypertension may be initiated with 37.5 mg/day - half the currently recommended dose.