A double-blind, placebo-controlled, cross-over trial of oral gallopamil was performed in 10 patients with stable angina. Gallopamil significantly increased mean exercise time and 1-mm ST time. The rate-pressure product was increased at 1-mm ST time, but unmodified at the highest comparable work load and at peak exercise. The ST segment depression was significantly reduced both at the highest comparable work load and at peak exercise. Gallopamil proves safe and effective; the mechanism of its anti-ischemic effect seems to be due both to an increase in myocardial oxygen supply and to a reduction in myocardial oxygen demand.