[Controlled study on the treatment of hypertension with verapamil in retard form]

The antihypertensive effect of an oral slow release (retard) formulation of verapamil was evaluated in a negative (placebo) and positive (nifedipine) controlled study. After a run-in period of one week without antihypertensive therapy, 54 patients were classified as having mild to moderate hypertension (diastolic blood pressure 95-115 mm Hg) and assigned randomly to one of three groups (n = 18 each). These received one of the following treatments over 2 weeks: either placebo b.i.d., or a nifedipine retard preparation 20 mg b.i.d., or a verapamil retard preparation 240 mg b.i.d. Assessments of blood pressure were made at rest and during a standardized bicycle stress test. Data were recorded at baseline and at the end of each week. After one week of treatment, 1 patient receiving nifedipine and 14 patients receiving placebo dropped out of the study because their diastolic pressures were equal to or above the values before treatment. After two weeks of treatment, 13 of 18 patients on verapamil and 9 of 18 patients on nifedipine had resting diastolic pressures less than or equal to 90 mm Hg. Also systolic pressure and blood pressures during exercise were significantly lowered by both active drugs. Verapamil caused a fall in heart rate during rest and under maximal exercise. Undesired side effects from verapamil were constipation (6 of 18) and headache (1 of 18); those from nifedipine were flush or headache (5 each of 18); ankle edema, dizziness, or tachycardia were each reported by one patient. In comparison with placebo values, verapamil lengthened the atrioventricular conduction time (PQ-interval) significantly, however, PQ-interval did not exceed 0.24 s.(ABSTRACT TRUNCATED AT 250 WORDS)