[Monotherapy of mild to moderate hypertension. Double-blind comparative study: amlodipine versus enalapril]

A double-blind multicenter study involving 89 patients with mild-to-moderate essential hypertension was performed to compare the efficacy and tolerability of amlodipine and enalapril. Following a placebo-controlled run-in phase, treatment was initiated with a daily dose 5 mg amlodipine or enalapril. In the second week of treatment, the daily dose of enalapril was increased to 10 mg. After two weeks of treatment, the amlodipine dose was increased from 5 to 10 mg, the enalapril dose from 10 to 20 mg if the diastolic seated blood pressure exceeded 90 mmHg.

Mean systolic and diastolic blood pressures decreased in the amlodipine group from, respectively, 158 +/- 17/101 +/- 6 mmHg to 142 +/- 14/87 +/- 11 mmHg, and in the enalapril group from 157 +/- 15/102 +/- 5 mmHg to 140 +/- 16/88 +/- 12 mmHg. The reduction in blood pressure was statistically significant in both groups (p < 0.0001), but the difference in blood pressure lowering effect of the two treatments was not statistically significant. The target blood pressure (diastolic BP seated < 90 mmHg) was achieved in 24 patients (75%) in the amlodipine group, and 23 patients (68%) in the enalapril group. Neither group experienced any severe adverse reactions. Side effects were seen in 3 patients of the amlodipine group and in 6 of the enalapril group.