In the setting of stable effort angina a single-blind, randomized, cross-over study to evaluate the effects of gallopamil (GAL) and amlodipine (AML) on exercise tolerance and ischemic ST depression was conducted. Fifteen outpatients, 12 males and 3 females, aged 40-65 years (57 +/- 9), with documented coronary atherosclerosis and reproducible ST-segment depression on 2 consecutive baseline exercise stress tests, completed the study, which consisted of 4 periods: 1 and 3 placebo, 2 and 4 at random GAL (50 mg tid) and AML (10 mg/daily). At the end of each period a multistage treadmill exercise stress test (Bruce protocol) was performed. Both drugs significantly (p = 0.0001) increased the ischemia time (IT) (0.1 mV ST depression) as compared to placebo, from 416 +/- 165 s to 635 +/- 161 s (GAL) and 607 +/- 152 s (AML) with significant difference (p = 0.2) between the 2 drugs, and reduced significantly (p = 0.001) the maximal ST depression from -0.25 +/- 0.09 mV to -0.11 +/- 0.08 mV (GAL) and -0.12 +/- 0.09 mV (AML). At the IT, the systolic blood pressure increased from 178 +/- 23 mmHg to 185 +/- 20 mmHg (GAL) and remained unchanged during AML treatment (178 +/- 15 mmHg); similarly, the heart rate increased from 126 +/- 22 b/min to 139 +/- 21 b/min (GAL) and 138 +/- 19 b/min (AML). In conclusion, both GAL and AML showed a good anti-ischemic effect (IT = +52.6% during GAL and +45.9% during AML), even if GAL proved to be significantly more effective than AML.