What are the contraindications of antiarrhythmic drugs?

Contraindications: Patients with severe sinus-node dysfunction, causing marked sinus bradycardia; second- and third-degree atrioventricular block; and when episodes of bradycardia have caused syncope (except when used in conjunction with a pacemaker). Patients with a known hypersensitivity to the drug.

Amiodarone is used in the treatment of atrial fibrillation, although the FDA has not approved this indication .

Amiodarone is considered the most potent antiarrhythmic agent. The adverse event profile with amiodarone can be intolerable, with gastrointestinal effects the most common side effect.