The pharmacokinetics and pharmacology of oral diltiazem in normal volunteers.

Oral diltiazem is being used increasingly in the treatment of Prinzmetal's angina. This study investigated the pharmacokinetics, electrocardiographic effects, and blood pressure responses of normal male volunteers to various single oral doses of diltiazem. Doses selected were 30, 60, 90, and 120 mg. Thirteen subjects received 30 mg. 12 subjects received 60 mg, 10 subjects received 90 mg diltiazem, and four subjects received 120 mg diltiazem AUCs for the 60, 90, and 120 mg doses were 565, 984, and 1258 ng/ml . hr, respectively. The values for t1/2, beta, and tmax were similar after each dosing.