Home Drug Guide Ibutilide fumarate

Drug Guide

Generic Name

Ibutilide fumarate

Brand Names Corvert

Classification

Therapeutic: Antiarrhythmic agent

Pharmacological: Class III antiarrhythmic, potassium channel blocker

FDA Approved Indications

Atrial fibrillation
Atrial flutter

Mechanism of Action

Ibutilide prolongs cardiac action potential duration by blocking potassium channels, which delays repolarization and prolongs the effective refractory period, thereby converting atrial arrhythmias to sinus rhythm.

Dosage and Administration

Adult: Typically 1 mg IV over 10 minutes; may repeat in 10-15 minutes if necessary, up to a maximum of 2 mg.

Pediatric: Not FDA approved; use is off-label and requires special considerations.

Geriatric: Adjust dosing carefully due to increased risk of adverse effects; close monitoring recommended.

Renal Impairment: Use with caution; no specific dose adjustment established.

Hepatic Impairment: Use caution; limited data.

Pharmacokinetics

Absorption: Not applicable (administered IV)

Distribution: Widely distributed, crosses blood-brain barrier

Metabolism: Metabolized in the liver by CYP3A4

Excretion: Excreted primarily in urine, with some biliary excretion

Half Life: Approximately 2-10 hours (average around 4 hours)

Contraindications

Long QT syndrome
Hypersensitivity to ibutilide
Recent myocardial infarction or heart surgery

Precautions

Risk of arrhythmias, including torsades de pointes; baseline ECG monitoring required.

Adverse Reactions - Common

Premature ventricular contractions (Frequent)
Torsades de pointes (a type of ventricular tachycardia) (Less common)

Adverse Reactions - Serious

Prolonged QT interval leading to torsades de pointes (Serious, with potential for fatality)
Heart failure or worsening arrhythmias (Rare)

Drug-Drug Interactions

Other QT-prolonging agents (e.g., amiodarone, sotalol)

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor ECG continuously during and after administration, especially QT interval.

Diagnoses:

Risk for ventricular arrhythmias

Implementation: Administer IV as prescribed; ensure cardiac monitoring during and for several hours post-infusion.

Evaluation: Assess for conversion of arrhythmia, monitor for adverse effects, and ensure stabilization before discharge.

Patient/Family Teaching

Report palpitations, dizziness, or chest pain immediately.
Follow instructions for monitoring and activity.
Inform about possible side effects, including dizziness or irregular heartbeat.

Special Considerations

Black Box Warnings:

Risk of life-threatening arrhythmias, including torsades de pointes, especially in patients with prolonged QT interval or electrolyte abnormalities.

Genetic Factors: Prolonged QT syndrome may increase risk.

Lab Test Interference: QT prolongation observed on ECG; monitor electrolytes (potassium, magnesium).

Overdose Management

Signs/Symptoms: Severe arrhythmias, hypotension, bradycardia.

Treatment: Discontinue drug, provide supportive care, correct electrolyte imbalances, and manage arrhythmias according to advanced cardiac life support (ACLS) protocols.

Storage and Handling

Storage: Store at room temperature away from moisture and light.

Stability: Stable under recommended storage conditions; use before expiration date.