Clinical study on the hypotensive effect of diltiazem hydrochloride.

Diltiazem HCl was administered p.o. at a fixed daily dose level of 180 mg to patients with essential hypertension, and the hypotensive effect of the drug was investigated. The following results were obtained: diltiazem HCl given alone exhibited a hypotensive effect on systolic pressure in 88.9% of the patients and on diastolic pressure in 66.7% of the patients. The concurrent use of diltiazem HCl with trichlormethiazide exerted a hypotensive effect on patients who were nonresponsive to diltiazem HCl alone. As regards side effects, one patient complained of gastric fullness and one of dizziness. However, the symptoms were so mild that further continuation of diltiazem HCl therapy was possible. From the results obtained, it is concluded that diltiazem HCl can effectively be used clinically as a hypotensive drug.