Home Drug Guide Rufinamide

Drug Guide

Generic Name

Rufinamide

Brand Names Banzel

Classification

Therapeutic: Anticonvulsant, Antiepileptic

Pharmacological: Sodium channel blocker

FDA Approved Indications

Lennox-Gastaut Syndrome

Mechanism of Action

Rufinamide prolongs the inactive state of voltage-gated sodium channels, stabilizing neuronal membranes and reducing excitability, thereby decreasing seizure activity.

Dosage and Administration

Adult: Initial dose is usually 45 mg/kg/day divided into two doses; the dose can be titrated up to a maximum of 3,200 mg/day based on response and tolerability.

Pediatric: Dosing is weight-based; initial dose of 10-45 mg/kg/day divided twice daily, titrated based on efficacy and tolerability.

Geriatric: Use with caution; start at lower doses and titrate slowly due to potential comorbidities and concomitant medications.

Renal Impairment: Adjust dose in patients with renal impairment; consultation with a nephrologist is advised.

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

Pharmacokinetics

Absorption: Well absorbed with an oral bioavailability of approximately 55%.

Distribution: Binding to plasma proteins is low (~20%).

Metabolism: Metabolized primarily via hydrolysis and oxidation; CYP3A4 involvement is minimal.

Excretion: Excreted mainly via the urine; unchanged and metabolites.

Half Life: Approximately 6 to 10 hours.

Contraindications

Hypersensitivity to rufinamide.
Severe hepatic impairment.

Precautions

Risk of QT shortening; monitor ECG periodically.
Teens and children with a history of familial short QT syndrome are at higher risk of arrhythmias.
Monitor for signs of hypersensitivity reactions, including rash, fever, lymphadenopathy, and eosinophilia.

Adverse Reactions - Common

Dizziness (Frequent)
Somnolence (Frequent)
Nausea (Frequent)
Vomiting (Frequent)
Fatigue (Frequent)

Adverse Reactions - Serious

QTC shortening leading to arrhythmias (Rare)
Serious hypersensitivity reactions (Rare)
Liver enzyme elevations (Rare)

Drug-Drug Interactions

Combination with other drugs that prolong QT interval may increase risk of arrhythmias.
CYP3A4 inducers or inhibitors can alter rufinamide levels.

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor for seizure frequency and adverse reactions, especially cardiological and hypersensitivity responses.

Diagnoses:

Risk for injury related to seizures or adverse drug effects.
Knowledge deficit regarding medication use.

Implementation: Administer with food to reduce gastrointestinal upset; Monitor ECG periodically; Educate about adherence and side effects.

Evaluation: Efficacy in seizure control; monitor for adverse reactions and drug interactions.

Patient/Family Teaching

Take medication exactly as prescribed.
Report any signs of rash, fever, hypersensitivity, or cardiac symptoms.
Avoid abrupt discontinuation.
Be aware of potential side effects like dizziness and somnolence.
Use additional contraceptive methods if applicable, as per prescribing info.

Special Considerations

Black Box Warnings:

None specifically for rufinamide, but caution with arrhythmogenic risk due to QT effects.

Genetic Factors: Patients with familial short QT syndrome are at increased risk of arrhythmias.

Lab Test Interference: May influence ECGs by causing QT shortening.

Overdose Management

Signs/Symptoms: Dizziness, drowsiness, ataxia, possibly seizures.

Treatment: Supportive care; activated charcoal if recent ingestion; cardiac monitoring for arrhythmias; no specific antidote.

Storage and Handling

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

Stability: Stable at room temperature for up to 24 months.