Atenolol: once-daily cardioselective beta blockade for angina pectoris.

Abstract
The physiology, pharmacokinetics and efficacy of atenolol [AT], a cardioselective .beta.-adrenergic blocking agent, were evaluated in 10 patients with stable angina pectoris in a single-blind, rose-ranging study. After a 1 mo. control placebo period, AT was administered once daily at dosages of 25, 50, 100 and 200 mg for 2 wk periods. All patients had fewer anginal attacks and consumed fewer nitroglycerin tablets than during the placebo period. Ambulatory ECG recordings [24 h] showed a decrease in mean hourly heart rate [HR] throughout the dosing period, with preservation of diurnal variation. Maximal, symptom-limited, treadmill exercise tests performed 3 h after drug ingestion showed significantly increased exercise time and decreased double products for all doses, but especially with 100 mg and 200 mg doses. Exercise time 24 h after drug ingestion continued to show a decrease in maximum HR and double product, with 100 mg and 200 mg doses again being most effective. AT serum levels correlated with percent reduction in exercise HR and increased exercise time. Serum levels rose linearly, with an average elimination half-life of about 10 h after chronic oral dosing. AT was an effective antianginal agent and suppressed resting and exercise-stressed HR for 24 h after ingestion when given in a 100 mg or 200 mg dose once daily.