A parallel group randomised comparative study of felodipine and nifedipine in hypertension.

We compared the antihypertensive effects and tolerability of a new calcium channel antagonist felodipine with nifedipine in an open randomised parallel group study in 49 patients with moderate hypertension (diastolic blood pressure 105-120 mm Hg). After two weeks run in period felodipine 5 mg and 10 mg once daily was compared with nifedipine 10 mg tid for an active treatment period of 4 weeks. Twenty three patients (mean age 42 +/- 10 years) received felodipine 5 mg once daily for first 2 weeks and 10 mg once daily for subsequent 2 weeks. Twenty six patients (mean age 45 +/- 9 years) received nifedipine 10 mg tid for 4 weeks. The mean reduction in supine diastolic blood pressure in two groups was 17 +/- 6 mm Hg (nifedipine) and 19 +/- 8 mm Hg (felodipine) (p = NS). The goal diastolic blood pressure of less than or equal to 90 mm Hg was achieved in 31 percent (nifedipine group) and 43.5 percent (felodipine group) of patients (p = NS). Side effects were common with both drugs; however, the tolerability was better with felodipine than with nifedipine. In conclusion felodipine was as effective as nifedipine and had the advantage of once a day dosage.