Sustained release verapamil in hypertension. Results from a noninvasive ambulatory blood pressure monitoring and a clinical study.

The antihypertensive effect of a new sustained-release matrix formulation of verapamil 200 mg was investigated in a dose-response study in patients with mild to moderate essential hypertension. Noninvasive ambulatory blood pressure measurements were recorded over 24 h in 6 patients with diastolic blood pressure greater than or equal to 100 mmHg. The patients received sustained-release verapamil 200 mg once daily and twice daily in a randomized order. Each medication period lasted 2 weeks. Verapamil 200 mg twice daily had a better antihypertensive effect than the same dose once daily. After a 6-week placebo period 27 patients with a diastolic blood pressure greater than or equal to 100 mmHg were included in a double-blind clinical trial. The patients received sustained release verapamil 200 mg once daily and twice daily in a randomized crossover manner. Each medication period lasted 6 weeks, with an intervening 6-week placebo period. A diastolic blood pressure of less than or equal to 95 mmHg was achieved in 6 patients with the once-daily regimen and in 14 with the twice-daily regimen. The mean fall in diastolic blood pressure was 4 and 9 mmHg, respectively (p less than 0.05). We conclude that sustained-release verapamil 200 mg once daily gives a satisfactory blood pressure response only in a minority of patients, while 200 mg twice daily has a significantly better antihypertensive effect. Both doses were well tolerated.