Amlodipine compared to nitrendipine for the treatment of mild-to-moderate hypertension.

This study compared the efficacy and safety of 8 weeks of open treatment with the dihydropyridine calcium antagonists amlodipine and nitrendipine in mild-to-moderate hypertension. Interim analysis of data from 74 patients (43 male, 31 female) showed that amlodipine normalized diastolic blood pressure (less than or equal to 90 mmHg) in 95% of patients compared with 83% of nitrendipine-treated patients. Nitrendipine produced a statistically significant increase in heart rate at 2 and 4 weeks of therapy but there was no significant change in heart rate in amlodipine-treated patients. Amlodipine-treated patients reported fewer adverse events (26%) than did the nitrendipine-treated group (47%), with two patients from the nitrendipine group discontinuing treatment due to treatment-related adverse events. Adverse events in the amlodipine-treated group were mild to moderate. The incidence of flushing was higher in nitrendipine-treated patients (25%) than in amlodipine-treated patients (10%). This relative difference in the incidence of vasodilator-related side effects is probably explained by the gradual onset of effect with amlodipine.