Monotherapy with felodipine, a new calcium antagonist, in mild and moderate hypertension.

The role of felodipine, a new calcium antagonist, in monotherapy for mild and moderate hypertension was investigated in a placebo-controlled double-blind study of 109 patients from 13 centres. The patients were randomised in a double-blind fashion to receive felodipine, 2.5 mg b.i.d. (32 patients), 5 mg b.i.d. (30 patients), 10 mg b.i.d. (24 patients), or placebo (23 patients). Two hours after the first tablet was administered, there was a reduction in systolic and diastolic blood pressure, both supine (p less than 0.05) and standing (p less than 0.001), that was significantly correlated with dose. Three and 8 weeks later, 2 h after dosage, this correlation was still apparent in both supine and standing blood pressure (p less than 0.001). One week after randomisation, at 12 hours after administration there was a significant correlation with dose in the standing systolic (p less than 0.05) and diastolic (p less than 0.01) blood pressure. After 8 weeks therapy, a significant correlation with dose occurred in both supine and standing systolic (p less than 0.05) and diastolic (p less than 0.01) blood pressure 12 h after therapy. The proportion of patients completing the study who achieved a supine diastolic blood pressure of 90 mm Hg or less after 8 weeks therapy at 2 h after dosage was 9% on placebo, 67% on felodipine 2.5 mg b.i.d., 57% on felodipine 5 mg b.i.d., and 92% on felodipine 10 mg b.i.d. Felodipine was generally well tolerated although 10 patients on the highest dose withdrew due to adverse experiences. Plasma felodipine levels were significantly correlated with dose.(ABSTRACT TRUNCATED AT 250 WORDS)