Once-daily treatment of essential hypertension with captopril

After a 4- to 6-week placebo lead-in period, 382 mild-to-moderate hypertensive patients with diastolic blood pressures remaining between 92 and 109 mmHg were randomized to double-blind treatment with captopril (50 mg q.d.) (94), captopril (50 mg b.i.d.) (97), captopril (50 mg q.d.) plus hydrochlorothiazide (97), and placebo (94). After 4 weeks the captopril dosage was doubled, whereas the hydrochlorothiazide dose remained at 25 mg for an additional 4 weeks. Response to treatment was evaluated by means of blood pressure determinations at the end of 4 and 8 weeks. All three active treatment regimens reduced diastolic blood pressure more than placebo did (p less than or equal to 0.01). Patients receiving captopril with diuretic had a greater decrease in pressure than those receiving captopril alone. The once-daily captopril regimen was as effective as the twice-daily regimen, although the latter employed double the daily dose. Increasing the captopril dosage during the second 4-week period resulted in a minimal addition reduction in blood pressure. Full 24-hour monitoring confirmed that the blood pressure was controlled by once-daily captopril therapy. Captopril given once daily, alone or in combination with hydrochlorothiazide, is efficacious treatment for patients with mild-to-moderate hypertension. The once-daily regimen should further enhance patient compliance.