Dose-response relation of the angiotensin converting enzyme inhibitor ramipril in mild to moderate essential hypertension

The effects of various dosage levels of ramipril on blood pressure were examined in a double-blind multicenter clinical trial. Patients with mild to moderate essential hypertension were first entered into a single-blind washout placebo phase of 4 weeks duration. The patients were then randomized to 1 of 3 treatment groups and received either 1.25, 2.5 or 5 mg of ramipril orally once a day for 6 weeks. After 6 weeks of treatment, the diastolic blood pressure had been decreased by 16.0 mm Hg (53 patients), 16.5 mm Hg (54 patients) and 19.9 mm Hg (53 patients) for the 1.25, 2.5 and 5 mg groups, respectively. Systolic blood pressure had decreased by an average of 22.5 mm Hg independent of the dose administered. Diastolic blood pressure was decreased to ≤90 mm Hg in 64%, 63% and 77% of the patients in the 3 groups, respectively. The differences in these percentages among the groups were not statistically significant. The tolerability of the drug was good; discontinuation of treatment was necessary for 1 patient in the 1.25 mg group and medication was lowered for 2 patients because of adverse reactions. There were no clinically significant changes of any laboratory variables, except for an increase in uric acid serum levels.