Disopyramide Phosphate

Disopyramide Phosphate is a class Ia anti-arrhythmic used in ventricular arrhythmias by stabilizing cardiac electrical activity.

Disopyramide phosphate is a class IA antiarrhythmic agent with a quinuclidine core structure. It features a dibenzodioxepin ring system linked to a quinuclidine moiety and a diethylamino group.
Chemical Formula: C₂₀H₂₉N₃O₄S·H₃PO₄

Class IA Antiarrhythmic: Inhibits fast sodium channels, prolongs action potential duration and refractory period.
Potassium Channel Blockade: Extends repolarization by blocking potassium efflux.
Anticholinergic Effects: Exhibits antimuscarinic activity, which can lead to side effects like dry mouth and blurred vision.
Effect on Heart Rate: Converts atrial fibrillation to sinus rhythm and prevents reentrant arrhythmias.

Ventricular Arrhythmias: Treats ventricular tachycardia and ventricular fibrillation.
Atrial Arrhythmias: Manages atrial fibrillation and atrial flutter.
Reentrant Arrhythmias Prevention: Effective in preventing recurrence post-cardiac events.
Antiarrhythmic Prophylaxis: Used after myocardial infarction to prevent arrhythmias.

Quinuclidine Core: Essential for blocking fast sodium channels and prolonging the action potential.
Dibenzodioxepin Ring System: Enhances lipophilicity, improving membrane permeability and binding affinity to cardiac ion channels.
Diethylamino Group: Increases affinity for sodium channels and contributes to antimuscarinic side effects.
Substituents: Modifications on the aromatic rings can influence potency and selectivity for ion channels.