Pharmacokinetics of beta-receptor-blocking agents in relation to their anti-hypertensive effect.
1. Beta-Recptor-blocking drugs are rapidly and completely absorbed after oral administration. Systemic availability is nevertheless incomplete for propranolol, alprenolol and oxprenolol, owing to "first-pass' extraction by the liver. 2. Plasma half-life is between 2 and 4 h, except for sotalol (10-12 h). Plasma elimination of propranolol is reduced with decreased liver blood flow observed in congestive heart failure or during chronic propranolol therapy itself. 3. beta-Receptor blockade is usually achieved in these concentration ranges: propranolol and alprenolol, 50-100 ng/ml; oxprenolol, 500-1000 ng/ml; pindolol, 10-30 ng/ml; sotalol, 2-6 microng/ml. Higher concentrations are often found with high doses administered to hypertensive patients.
D000284:Administration, Oral; D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000097:blood*; D001682:Biological Availability; D006207:Half-Life; D006973:Hypertension / Q000188:drug therapy; D008099:Liver / Q000378:metabolism
D000319:Adrenergic beta-Antagonists