Comparative clinical study of amlodipine and nifedipine in patients with mild to moderate essential hypertension

Amlodipine, a new long-acting dihydropyridine calcium antagonist, was compared with nifedipine retard in a short-term study of 40 out-patients with mild to moderate essential hypertension. After two weeks of single-blind placebo run-in, patients were randomly allocated to receive amlodipine (5 to 10 mg once daily, 20 patients) or nifedipine R (20 mg BID, 20 patients). At the end of the study (at week 12) there were clinically significant reductions in 24-hour postdose blood pressure with amlodipine (-19.5/-13.3 mmHg) and in 12-hour postdose blood pressure with nifedipine retard (-20.6/-17 mmHg). Neither amlodipine nor nifedipine retard produced clinically significant changes in pulse rate or electrocardiogram. The incidence of side effects was comparable in the two groups. Amlodipine was an effective, well-tolerated agent for the treatment of mild to moderate hypertension in this study as single daily dose monotherapy.