Comparative study of the effects of penbutolol and propranolol in the treatment of angina pectoris.

1. Fourteen patients with angina with obstructive coronary artery disease were treated with propranolol, given four times daily, or penbutolol given once daily. 2. The frequency of anginal episodes and glyceryl trinitrate consumption were monitored using diary cards. Heart rate and blood pressure were recorded at rest and on exercise. Left ventricular function was assessed using systolic time intervals. 3. Penbutolol given once daily showed similar effects as propranolol, using both clinical assessment and changes in physiological parameters.