Comparison of diltiazem and nifedipine alone and in combination in patients with coronary artery spasm

Fifteen patients with coronary artery spasm completed a double-blind placebo-controlled trial comparing diltiazem and nifedipine. Increasingly, higher daily doses (diltiazem, 90 to 360 mg; nifedipine, 30 to 120 mg) were administered to achieve optimal clinical effects. Daily diaries and ambulatory electrocardiographic recordings were used to assess efficacy and side effects. Both drugs significantly decreased angina frequency compared with that in the preceding placebo period (diltiazem 1.4 ± 0.4 [mean ± SEM] to 0.4 ± 0.2 episodes per day; nifedipine 1.4 ± 0.3 to 0.4 ± 0.1 episodes per day; both p Diltiazem was discontinued in one patient because of urticaria, but the total number of side effects was higher with nifedipine (12 of 15 patients) than with diltiazem (5 of 15, p Both diltiazem and nifedipine provide effective antianginal therapy for coronary spasm, but diltiazem has fewer side effects. The combination of these drugs is associated with frequent side effects but helps some patients who remain symptomatic despite maximal tolerated doses of a single drug.