We studied the short-term effects of oral administration of nisoldipine (10 mg) and propranolol (80 mg) alone and in combination in 14 patients with chronic exertional angina pectoris in a double-blind, randomized, cross-over study. The 14 patients (13 men and 1 woman, mean age 56 +/- 7 years) performed symptoms-limited bicycle exercise stress test 3 h after placebo or active substance administration. Maximal work load, exercise duration, and time to 1-mm ST segment depression were significantly increased and ST depression at peak exercise was significantly decreased by drugs alone and in combination. Propranolol and nisoldipine alone improved exercise duration similarly and as well as the combination; however, a different response to the three pharmacologic interventions was found in patients treated with single drugs. The improvement in exercise tolerance was associated with rate-pressure product values at peak exercise, unchanged after nisoldipine and significantly reduced after both propranolol alone and in combination. After placebo, all patients had exercise-induced angina, in 9, 8, and 4 patients after nisoldipine, propranolol, and the combination of the two drugs, respectively. Nisoldipine is effective in the treatment of effort angina and its combination with propranolol may be useful and superior in patients who show poor response to monotherapy.