Corvert

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Tell your caregivers at once if you have:

• headache with chest pain and severe dizziness;

• shortness of breath; or

• a light-headed feeling, like you might pass out.

Common side effects may include:

• mild headache; or

• nausea.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Class III antiarrhythmic agent;1 2 3 4 7 a methanesulfonanilide derivative.1 2 3

Supraventricular Tachyarrhythmias

Used for rapid conversion of recent-onset atrial fibrillation or flutter to sinus rhythm.1 7 300 301

Considered a drug of choice for pharmacologic cardioversion of atrial fibrillation or flutter.300 301

Some experts state that ibutilide also may be used in hemodynamically stable patients with preexcited atrial fibrillation and rapid ventricular response (e.g., Wolff-Parkinson-White syndrome†).300 301

Also may be used in selected patients with focal atrial tachycardia†.300

Atrial arrhythmias that are not of recent onset are less likely to respond to the drug.1 Efficacy not determined in atrial arrhythmias of >90 days’ duration.1

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

• Tell all of your health care providers that you take Corvert. This includes your doctors, nurses, pharmacists, and dentists.
• Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using this medicine while you are pregnant.

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Chest pain or pressure.
• Fast or slow heartbeat.
• A new or worse heartbeat that does not feel normal.
• Dizziness or passing out.

• If you need to store this medicine at home, talk with your doctor, nurse, or pharmacist about how to store it.

Proarrhythmia

Like other antiarrhythmic agents, Corvert Injection can induce or worsen ventricular arrhythmias in some patients. This may have potentially fatal consequences. Torsades de pointes, a polymorphic ventricular tachycardia that develops in the setting of a prolonged QT interval, may occur because of the effect Corvert has on cardiac repolarization, but Corvert can also cause polymorphic VT in the absence of excessive prolongation of the QT interval. In general, with drugs that prolong the QT interval, the risk of torsades de pointes is thought to increase progressively as the QT interval is prolonged and may be worsened with bradycardia, a varying heart rate, and hypokalemia. In clinical trials conducted in patients with atrial fibrillation and atrial flutter, those with QTc intervals >440 msec were not usually allowed to participate, and serum potassium had to be above 4.0 mEq/L. Although change in QTc was dose dependent for ibutilide, there was no clear relationship between risk of serious proarrhythmia and dose in clinical studies, possibly due to the small number of events. In clinical trials of intravenous ibutilide, patients with a history of congestive heart failure (CHF) or low left ventricular ejection fraction appeared to have a higher incidence of sustained polymorphic ventricular tachycardia (VT), than those without such underlying conditions; for sustained polymorphic VT the rate was 5.4% in patients with a history of CHF and 0.8% without it. There was also a suggestion that women had a higher risk of proarrhythmia, but the sex difference was not observed in all studies and was most prominent for nonsustained ventricular tachycardia. The incidence of sustained ventricular arrhythmias was similar in male (1.8%) and female (1.5%) patients, possibly due to the small number of events. Corvert is not recommended in patients who have previously demonstrated polymorphic ventricular tachycardia (eg, torsades de pointes).

During registration trials, 1.7% of patients with atrial flutter or atrial fibrillation treated with Corvert developed sustained polymorphic ventricular tachycardia requiring cardioversion. In these clinical trials, many initial episodes of polymorphic ventricular tachycardia occurred after the infusion of Corvert was stopped but generally not more than 40 minutes after the start of the first infusion. There were, however, instances of recurrent polymorphic VT that occurred about 3 hours after the initial infusion. In two cases, the VT degenerated into ventricular fibrillation, requiring immediate defibrillation. Other cases were managed with cardiac pacing and magnesium sulfate infusions. Nonsustained polymorphic ventricular tachycardia occurred in 2.7% of patients and nonsustained monomorphic ventricular tachycardias occurred in 4.9% of the patients (see ADVERSE REACTIONS).

Proarrhythmic events must be anticipated. Skilled personnel and proper equipment, including cardiac monitoring equipment, intracardiac pacing facilities, a cardioverter/defibrillator, and medication for treatment of sustained ventricular tachycardia, including polymorphic ventricular tachycardia, must be available during and after administration of Corvert. Before treatment with Corvert, hypokalemia and hypomagnesemia should be corrected to reduce the potential for proarrhythmia. Patients should be observed with continuous ECG monitoring for at least 4 hours following infusion or until QTc has returned to baseline. Longer monitoring is required if any arrhythmic activity is noted. Management of polymorphic ventricular tachycardia includes discontinuation of ibutilide, correction of electrolyte abnormalities, especially potassium and magnesium, and overdrive cardiac pacing, electrical cardioversion, or defibrillation. Pharmacologic therapies include magnesium sulfate infusions. Treatment with antiarrhythmics should generally be avoided.

Use should be avoided. Excreted into human milk: Unknown Excreted into animal milk: Data not available Comments: The effects in the nursing infant are unknown.