Last reviewed 2026-04-22 · How we verify

Amiodarone Injectable Solution

Amiodarone is a Class III antiarrhythmic agent that blocks potassium channels and prolongs the action potential duration and refractory period to restore normal heart rhythm.

Amiodarone is a Class III antiarrhythmic agent that blocks potassium channels and prolongs the action potential duration and refractory period to restore normal heart rhythm. Used for Ventricular fibrillation, Ventricular tachycardia, Atrial fibrillation with rapid ventricular response.

At a glance

Mechanism of action

Amiodarone works primarily by blocking cardiac potassium channels, which delays repolarization and extends the action potential duration. It also has properties of Classes I, II, and IV antiarrhythmics, providing additional effects on sodium and calcium channels as well as beta-adrenergic blockade. This multi-channel activity makes it effective for suppressing various types of cardiac arrhythmias.

Approved indications

• Ventricular fibrillation
• Ventricular tachycardia
• Atrial fibrillation with rapid ventricular response
• Supraventricular tachycardia

Common side effects

• Hypotension
• Bradycardia
• Phlebitis at injection site
• Nausea
• Pulmonary toxicity (chronic use)
• Thyroid dysfunction (chronic use)
• Hepatotoxicity

Key clinical trials

• Flecainide Versus Amiodarone in the Cardioversion of Paroxysmal Atrial Fibrillation at the Emergency Department, in Patients With Coronary Artery Disease Without Residual Ischemia (PHASE3)
• Refralon Versus Amiodarone for Cardioversion of Paroxysmal Fibrillation and Atrial Flutter (PHASE4)
• Evaluation of the Efficacy and Safety of Nifekalant Hydrochloride (NIF) Injection. (PHASE4)

Primary sources

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