Ibutilide

An article about the antiarrhythmic medication Ibutilide

Ibutilide

Ibutilide is a class III antiarrhythmic agent used in the treatment of atrial fibrillation and atrial flutter. It is administered intravenously and works by prolonging the cardiac action potential, thereby helping to restore normal heart rhythm.

Mechanism of Action

Ibutilide functions by blocking specific potassium channels in the heart, which are responsible for repolarization during the cardiac action potential. By inhibiting these channels, ibutilide prolongs the action potential duration and refractory period, which can help terminate reentrant arrhythmias such as atrial fibrillation and atrial flutter.

Clinical Use

Ibutilide is primarily used in the acute setting to convert atrial fibrillation or atrial flutter to normal sinus rhythm. It is administered as an intravenous infusion, typically in a hospital setting where the patient can be monitored for potential adverse effects.

Adverse Effects

The most significant adverse effect of ibutilide is the risk of torsades de pointes, a type of ventricular tachycardia that can lead to ventricular fibrillation and sudden cardiac death. Other side effects may include hypotension, bradycardia, and QT interval prolongation.

Pharmacokinetics

Ibutilide is rapidly distributed following intravenous administration, with a half-life of approximately 6 hours. It is metabolized in the liver and excreted primarily in the urine.

Contraindications

Ibutilide is contraindicated in patients with a prolonged QT interval, congestive heart failure, or a history of torsades de pointes. Caution is advised when using ibutilide in conjunction with other medications that prolong the QT interval.

Related pages

• Atrial fibrillation
• Atrial flutter
• Antiarrhythmic agent
• Torsades de pointes

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  Ibutilide