Sotalol

Sotalol is a non-selective beta-blocker (non-selective beta-blocker) and a potassium channel blocker (potassium channel blocker). Beta1-adrenergic receptors are mainly distributed in the sinoatrial node and atrioventricular node, whereas beta2-adrenergic receptors are distributed in atrial and ventricular myocardium, vascular smooth muscle, and bronchial smooth muscle. Both receptor types are Gs protein-coupled receptors. When sotalol blocks beta1 and beta2 receptors, it reduces sinoatrial node automaticity and slows atrioventricular nodal conduction. Sotalol also blocks the rapid delayed rectifier potassium current in cardiomyocytes, prolonging action potential duration and extending the effective refractory period.