No

Antiarrhythmic Agent, Class III

Acute termination of atrial fibrillation or flutter of recent onset; the effectiveness of ibutilide has not been determined in patients with arrhythmias >90 days in duration

C

Clinical effects on the fetus: Teratogenic and embryocidal in rats; avoid use in pregnancy

Breast-feeding/lactation: Avoid breast-feeding during therapy

Hypersensitivity to ibutilide or any component; QTc >440 msec

Potentially fatal arrhythmias (eg, polymorphic ventricular tachycardia) can occur with ibutilide, usually in association with torsade de pointes (QT prolongation). Studies indicate a 1.7% incidence of arrhythmias in treated patients. The drug should be given in a setting of continuous EKG monitoring and by personnel trained in treating arrhythmias particularly polymorphic ventricular tachycardia. Patients with chronic atrial fibrillation may not be the best candidates for ibutilide since they often revert after conversion and the risks of treatment may not be justified when compared to alternative management. Dosing adjustments are not required in patients with renal or hepatic dysfunction since a maximum of only two 10-minute infusions are utilized. Drug distribution, rather than administration, is one of the primary mechanisms responsible for termination of the pharmacologic effect. Safety and efficacy in children have not been established. Avoid any drug that can prolong QT interval. Correct hyperkalemia and hypomagnesemia before using. Monitor for heart block.

1% to 10%:

Cardiovascular: Sustained polymorphic ventricular tachycardia (ie, torsade de pointes) (1.7% - often requiring cardioversion), nonsustained polymorphic ventricular tachycardia (2.7%), nonsustained monomorphic ventricular tachycardia (4.9%), ventricular extrasystoles (5.1%), nonsustained monomorphic VT (4.9%), tachycardia/supraventricular tachycardia (2.7%), hypotension (2%), bundle branch block (1.9%), A-V block (1.5%), bradycardia (1.2%), QT segment prolongation, hypertension (1.2%), palpitations (1%)

Central nervous system: Headache (3.6%)

Gastrointestinal: Nausea (>1%)

<1% (Limited to important or life-threatening symptoms): Supraventricular extrasystoles (0.9%), nodal arrhythmia (0.7%), congestive heart failure (0.5%), syncope (0.3% - not > placebo), idioventricular rhythm (0.2%), sustained monomorphic ventricular tachycardia (0.2%), renal failure (0.3%)

Case reports: Erythematous bullous lesions

Symptoms include CNS depression, rapid gasping breathing, and convulsions; arrhythmias occur

Treatment is supportive and includes measures appropriate for the condition; antiarrhythmics are generally avoided; pharmacologic therapies may include magnesium sulfate, correction of other electrolyte abnormalities, overdrive cardiac pacing, electrical cardioversion, or defibrillation

Antiarrhythmics: Class Ia antiarrhythmic drugs (disopyramide, quinidine, and procainamide) and other class III drugs such as amiodarone and sotalol, should not be given concomitantly with ibutilide due to their potential to prolong refractoriness.

Other drugs which may prolong QT interval: phenothiazines, tricyclic and tetracyclic antidepressants, and cisapride, sparfloxacin, gatifloxacin, moxifloxacin, erythromycin may increase risk of toxicity; avoid concurrent use.

Digoxin: Signs of digoxin toxicity may be masked when coadministered with ibutilide.

Admixtures are chemically and physically stable for 24 hours at room temperature and for 48 hours at refrigerated temperatures

Exact mechanism of action is unknown; prolongs the action potential in cardiac tissue

Onset of effect: Within 90 minutes after start of infusion (1/2 of conversions to sinus rhythm occur during infusion)

Absorption: Onset: Within 90 minutes after start of infusion (1/2 of conversions to sinus rhythm occur during infusion)

Metabolism: Extensively metabolized in the liver

Half-life: 2-12 hours (average: 6 hours)

Elimination: Parent and metabolite excreted predominantly in the urine

I.V.: Initial:

greater than or equal to 60 kg: 1 mg over 10 minutes

If the arrhythmia does not terminate within 10 minutes after the end of the initial infusion, a second infusion of equal strength may be infused over a 10-minute period

Observe patient with continuous EKG monitoring for at least 4 hours following infusion or until QT_c has returned to baseline; skilled personnel and proper equipment should be available during administration of ibutilide and subsequent monitoring of the patient

Ibutilide may be use for pharmacologic cardioversion of atrial fibrillation or flutter. However a significant problem associated with therapy is torsade de pointes. It is important that the administration of ibutilide be carried out under closely monitored conditions and that facilities for cardiopulmonary resuscitation be at the bedside. It is also important that all precautionary measures for standard electrical cardioversion (eg, electrolytes, thromboembolic precautions, etc) be maintained.

None reported

Concurrent use with phenothiazine and antidepressants may produce prolongation of the Q-T interval; use combination with caution; consider a nonphenothiazine antipsychotic

No information available to require special precautions

No effects or complications reported

This drug is only given I.V. and you will be on continuous cardiac monitoring during and for several hours following administration. You may experience headache or irregular heartbeat during infusion. Report chest pain or respiratory difficulty immediately. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to be pregnant. Do not breast-feed.

See Monitoring Parameters; EKG, electrolytes

Injection, as fumarate: 0.1 mg/mL (10 mL)