What is the recommended dosing for Trileptal (oxcarbazepine) in a patient with epilepsy or bipolar disorder?

Trileptal (Oxcarbazepine) Dosing

For adults with epilepsy, start Trileptal at 600 mg/day divided twice daily and titrate by 300-600 mg/day at weekly intervals to a target maintenance dose of 1,200 mg/day, with a maximum of 2,400 mg/day if needed for seizure control. 1

Adult Dosing for Epilepsy

Adjunctive Therapy

• Initial dose: 600 mg/day divided twice daily 1
• Titration: Increase by maximum 600 mg/day at approximately weekly intervals 1
• Target maintenance: 1,200 mg/day 1
• Maximum dose: 2,400 mg/day (though most patients cannot tolerate this due to CNS effects) 1

Monotherapy (Converting from Other Antiepileptics)

• Initial dose: 600 mg/day divided twice daily 1
• Titration: Increase by 600 mg/day at weekly intervals 1
• Target maintenance: 2,400 mg/day over 2-4 weeks 1
• Concomitant drug withdrawal: Taper other antiepileptics completely over 3-6 weeks while increasing oxcarbazepine 1

Monotherapy (Treatment-Naive Patients)

• Initial dose: 600 mg/day divided twice daily 1
• Titration: Increase by 300 mg/day every third day 1
• Target maintenance: 1,200 mg/day 1

Pediatric Dosing for Epilepsy

Children Aged 4-16 Years (Adjunctive Therapy)

• Initial dose: 8-10 mg/kg/day (not to exceed 600 mg/day), divided twice daily 1
• Target maintenance (achieved over 2 weeks): 1
  • 20-29 kg: 900 mg/day
  • 29.1-39 kg: 1,200 mg/day

  • 39 kg: 1,800 mg/day

• Median effective dose: 31 mg/kg/day (range 6-51 mg/kg) 1

Children Aged 2 to <4 Years (Adjunctive Therapy)

• Initial dose: 8-10 mg/kg/day (not to exceed 600 mg/day), divided twice daily 1
• For patients <20 kg: Consider starting at 16-20 mg/kg/day 1
• Maximum maintenance: 60 mg/kg/day achieved over 2-4 weeks 1
• Note: Children 2-4 years may require up to twice the dose per body weight compared to adults 1

Children Aged 4-16 Years (Monotherapy)

• Initial dose: 8-10 mg/kg/day divided twice daily 1
• Titration: Increase by 5 mg/kg/day every third day 1
• Target maintenance: Weight-based (600-2,100 mg/day depending on weight) 1

Special Populations

Renal Impairment

• For creatinine clearance <30 mL/min: Start at 300 mg/day (half the usual starting dose) divided twice daily 1
• Titration: Increase slowly to achieve desired clinical response 1
• Rationale: Elimination half-life is prolonged with 2-fold increase in drug exposure 2

Hepatic Impairment

• Mild-to-moderate hepatic impairment: No dose adjustment needed 2

Important Clinical Considerations

Drug Interactions Requiring Dose Adjustment

• Strong CYP3A4 or UGT inducers (carbamazepine, phenobarbital, phenytoin): These reduce MHD levels by 30-40%; may need higher oxcarbazepine doses 1, 2
• High-dose oxcarbazepine (>1,200 mg/day): Can increase phenytoin levels by 40% and phenobarbital by 15%; phenytoin dose adjustment may be required 2

Monitoring Requirements

• Hyponatremia: Develops in approximately 3% of patients during first months of therapy 3
• Baseline sodium: Only measure if patient has renal disease, takes medications that lower sodium (diuretics, oral contraceptives, NSAIDs), or has symptoms of hyponatremia 3
• During maintenance: Monitor sodium if adding medications that decrease sodium or if symptoms develop 3

Administration

• Can be taken with or without food 1
• Oral suspension and tablets are interchangeable at equal doses 1

Common Pitfalls

• Oral contraceptive failure: Oxcarbazepine decreases ethinylestradiol and levonorgestrel levels; alternative contraception methods should be used 2, 4
• Faster titration option: In adults, can start with 150 mg/day at night and increase by 150 mg/day every second day, or start with up to 600 mg/day with weekly increments of 600 mg/day 3
• Children require higher weight-based doses: Children 4-12 years may need 50% higher doses per body weight than adults 1

Note on Bipolar Disorder

The FDA-approved labeling for oxcarbazepine does not include bipolar disorder as an indication 1. The drug is approved specifically for partial seizures in epilepsy 1, 2.