Amiodarone HCl injection is indicated for initiation of treatment and prophylaxis of frequently recurring ventricular fibrillation and hemodynamically unstable ventricular tachycardia in patients refractory to other therapy.

Intravenous amiodarone also can be used to treat patients with VT/VF for whom oral amiodarone is indicated, but who are unable to take oral medication.

During or after treatment with intravenous amiodarone, patients may be transferred to oral amiodarone therapy(see DOSAGE AND ADMINISTRATION).

Intravenous amiodarone should be used for acute treatment until the patient’s ventricular arrhythmias are stabilized.

Most patients will require this therapy for 48 to 96 hours, but intravenous amiodarone may be safely administered for longer periods if necessary.

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Ventricular Fibrillation -- A potentially lethal cardiac arrhythmia that is characterized by uncoordinated extremely rapid firing of electrical impulses (400-600/min) in HEART VENTRICLES. Such asynchronous ventricular quivering or fibrillation prevents any effective cardiac output and results in unconsciousness (SYNCOPE). It is one of the major electrocardiographic patterns seen with CARDIAC ARREST.

Tachycardia, Ventricular -- An abnormally rapid ventricular rhythm usually in excess of 150 beats per minute. It is generated within the ventricle below the BUNDLE OF HIS, either as autonomic impulse formation or reentrant impulse conduction. Depending on the etiology, onset of ventricular tachycardia can be paroxysmal (sudden) or nonparoxysmal, its wide QRS complexes can be uniform or polymorphic, and the ventricular beating may be independent of the atrial beating (AV dissociation).

Ventricular arrhythmia -- Irregular heart beat resulting from a pathologic process in the cardiac ventricles.--2004

Amiodarone injection is contraindicated in patients with known hypersensitivity to any of the components of amiodarone injection, including iodine, or in patients with cardiogenic shock, marked sinus bradycardia, and second- or third-degree AV block unless a functioning pacemaker is available.

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Hypersensitivity -- Altered reactivity to an antigen, which can result in pathologic reactions upon subsequent exposure to that particular antigen.

Cardiogenic shock -- Shock resulting from diminution of cardiac output in heart disease.

Sinus bradycardia -- A heart rate of less than 60 beats per minute, with its origin in the sinus node. (NCI)

Complete atrioventricular block -- Complete failure of atrial electrical impulse conduction through the AV node to the ventricles.

Hypotension Hypotension is the most common adverse effect seen with intravenous amiodarone.

In clinical trials, treatment-emergent, drug-related hypotension was reported as an adverse effect in 288 (16%) of 1836 patients treated with intravenous amiodarone.

Clinically significant hypotension during infusions was seen most often in the first several hours of treatment and was not dose related, but appeared to be related to the rate of infusion.

Hypotension necessitating alterations in intravenous amiodarone therapy was reported in 3% of patients, with permanent discontinuation required in less than 2% of patients.

Hypotension should be treated initially by slowing the infusion; additional standard therapy may be needed, including the following: vasopressor drugs, positive inotropic agents, and volume expansion.

The initial rate of infusion should be monitored closely and should not exceed that prescribed in DOSAGE AND ADMINISTRATION.

In some cases, hypotension may be refractory resulting in fatal outcome (see ADVERSE REACTIONS, Postmarketing Reports).

Bradycardia and AV Block Drug-related bradycardia occurred in 90 (4.9%) of 1836 patients in clinical trials while they were receiving intravenous amiodarone for life-threatening VT/VF; it was not dose-related.

Bradycardia should be treated by slowing the infusion rate or discontinuing amiodarone.

In some patients, inserting a pacemaker is required.

Despite such measures, bradycardia was progressive and terminal in 1 patient during the controlled trials.

Patients with a known predisposition to bradycardia or AV block should be treated with intravenous amiodarone in a setting where a temporary pacemaker is available.

Long-Term Use See labeling for oral amiodarone.

There has been limited experience in patients receiving intravenous amiodarone for longer than 3 weeks. Neonatal Hypo- or Hyperthyroidism Although amiodarone use during pregnancy is uncommon, there have been a small number of published reports of congenital goiter/hypothyroidism and hyperthyroidism associated with its oral administration.

If intravenous amiodarone is administered during pregnancy, the patient should be apprised of the potential hazard to the fetus.

The following US Branded drugs contain Amiodarone Hydrochloride

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CORDARONE -- WYETH PHARMACEUTICALS INC

NEXTERONE -- PRISM PHARMACEUTICALS INC

PACERONE -- UPSHER SMITH LABORATORIES INC