Diltiazem compared with hydrochlorothiazide in the treatment of mild-to-moderate essential hypertension

The efficacy of diltiazem (DTZ) (Tilazem; Parke-Davis) 90-180 mg twice daily was compared with that of hydrochlorothiazide (HCT) 25-50 mg once daily in the monotherapy of mild-to-moderate essential hypertension using a double-blind, double-dummy technique. Twenty-nine patients were randomly assigned to two groups and after a 4-week placebo period treated with HCT 25 mg once daily or DTZ 90 mg twice daily for 12 weeks. Dosage was doubled at week 8 in non-responders. Cross-over of therapy took place after a 4-week placebo washout. Both drugs effectively reduced raised arterial pressures with little change in pulse rate. HCT caused a slight elevation of the mean serum urate level. The study confirms that diltiazem offers an effective well-tolerated monotherapy for essential hypertension.