Dose-response studies of indenolol, a beta adrenoceptor blocker

Two studies were conducted on indenolol, a new beta-adrenoceptor blocker. In the first, nine healthy men received indenolol 40, 80, 160, and 320 mg and placebo orally. Two hours later a standard exercise test was performed, and systolic blood pressure, heart rate, and peak expiratory flow rate were recorded. Indenolol induced attenuation of exercise-induced rise in systolic blood pressure and tachycardia. In the second study, seven healthy men received indenolol 40, 80, 160, and 320 mg and propranolol 40, 80, 160, and 320 mg in randomized order. Dose-response curves for both drugs revealed that maximum attenuation of exercise tachycardia and systolic blood pressure were in the same range but suggested that indenolol induced a greater response in the lower doses. Neither drug had any effect on the exercise-induced rise in peak expiratory flow rate. Indenolol was well tolerated.