rufinamide


rufinamide

(roo-fin-a-mide) rufinamide,

Banzel

(trade name)

Classification

Therapeutic: anticonvulsants
Pharmacologic: triazoles
Pregnancy Category: C

Indications

Adjunctive treatment of seizures associated with Lennox-Gastaut syndrome in patients >4 yr.

Action

Although antiepileptic mechanism is unknown, rufinamide modulates the activity of sodium channels, prolonging the inactive state of the channel.

Therapeutic effects

Decreased incidence and severity of seizures associated with Lennox-Gastaut syndrome.

Pharmacokinetics

Absorption: 85% absorbed following oral administration; food enhances absorption.Distribution: Evenly distributed between erythrocytes and plasma.Metabolism and Excretion: Extensively metabolized; metabolites are primarily renally excreted.Half-life: 6–10 hr.

Time/action profile

ROUTEONSETPEAKDURATION
POunknown4–6 hr12 hr

Contraindications/Precautions

Contraindicated in: Hypersensitivity; Familial short QT syndrome; Severe hepatic impairment.Use Cautiously in: All patients (may ↑ risk of suicidal thoughts/behaviors); Mild to moderate hepatic impairment.

Adverse Reactions/Side Effects

Central nervous system

  • suicidal thoughts (life-threatening)
  • dizziness (most frequent)
  • fatigue (most frequent)
  • headache (most frequent)
  • somnolence (most frequent)

Ear, Eye, Nose, Throat

  • diplopia

Cardiovascular

  • QT prolongation

Gastrointestinal

  • nausea (most frequent)
  • changes in appetite

Genitourinary

  • urinary frequency

Dermatologic

  • rash

Hematologic

  • anemia

Neurologic

  • ataxia
  • coordination abnormalities
  • gait disturbances

Miscellaneous

  • Multi-organ hypersensitivity reactions (life-threatening)
  • hypersensitivity reactions (↑ in children)

Interactions

Drug-Drug interaction

Potent inducers of the CYP450 enzyme including carbamazepine, phenytoin, primidone, and phenobarbital ↑ clearance and may ↓ blood levels.Valproate ↓ clearance and may ↑ blood levels; valproate should be started at a low dose in patients stabilized on rufinamide. In patients stabilized on valproate, rufinamide should be started at a low dose.May ↓ blood levels and effectiveness of hormonal contraceptives.May ↑ blood levels of phenytoin.

Route/Dosage

Oral (Adults) 400–800 mg/day in two divided doses, ↑ by 400–800 mg every 2 days until a maximum daily dose of 3200 mg/day (1600 mg twice daily) is reached.Oral (Children ≥ 4 yr) 10 mg/kg/day in two divided doses, ↑ by 10 mg/kg every 2 days until a maximum daily dose of 45 mg/kg/day or 3200 mg/day given in 2 divided doses, whichever is less, is reached.

Availability

Tablets: 100 mg, 200 mg, 400 mg Oral suspensionorange-flavor: 40 mg/mL

Nursing implications

Nursing assessment

  • Assess location, duration, and characteristics of seizure activity. Institute seizure precautions.
  • Monitor closely for notable changes in behavior that could indicate the emergence or worsening of suicidal thoughts or behavior or depression.
  • Lab Test Considerations: May cause leukopenia, anemia, neutropenia, and thrombocytopenia.

Potential Nursing Diagnoses

Risk for injury (Indications)

Implementation

  • Oral: Administer with food. Tablets can be cut in half for dosing flexibility. Tablets may be administered as whole or half tablets, or crushed.

Patient/Family Teaching

  • Instruct patient to take rufinamide around the clock, as directed. Medication should be gradually discontinued over by 25% every 2 days to prevent seizures. Advise patient to read the Medication Guide before starting therapy and with each Rx refill.
  • May cause drowsiness, dizziness, ataxia, and incoordination. Caution patient to avoid driving or other activities requiring alertness until response to medication is known. Tell patient not to resume driving until physician gives clearance based on control of seizure disorder.
  • Inform patients and families of risk of suicidal thoughts and behavior and advise that behavioral changes, emergency or worsening signs and symptoms of depression, unusual changes in mood, or emergence of suicidal thoughts, behavior, or thoughts of self-harm should be reported to health care professional immediately.
  • Instruct patient to notify health care professional if signs of multiorgan hypersensitivity reactions (fever, rash, fatigue, jaundice, dark urine) occur.
  • Instruct patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and consult health care professional before taking any new medications and to avoid taking alcohol or other CNS depressants concurrently with rufinamide.
  • Advise female patients to notify health care professional if pregnancy is planned or suspected or if breastfeeding. Use of rufinamide decreases effectiveness of oral contraceptives. Advise patient to use a nonhormonal method of contraception during therapy.

Evaluation/Desired Outcomes

  • Decreased frequency and intensity of seizure activity.