Oxcarbazepine

Administration

• Type: anti epileptic
• Dosage Forms: 150,300,600; 300/5 mL
• Routes of Administration: PO
• Common Trade Names: Trileptal

Adult Dosing

Partial seizures

• adjunct tx: Dose: 600 mg PO bid; Start: 300 mg PO bid, incr. by up to 600 mg/day qwk; Max: 2400 mg/day;
• conversion to monotherapy: Dose: 1200 mg PO bid; Start: 300 mg PO bid, incr. by up to 600 mg/day qwk; Max: 2400 mg/day; D/C concomitant anticonvulsants over 3-6wk; taper dose gradually to D/C
• initial monotherapy: Dose: 600 mg PO bid; Start: 300 mg PO bid, incr. by 300 mg/day q3 days; Max: 2400 mg/day

Trigeminal neuralgia

• 450-1200 mg PO bid
• Start: 300 mg PO bid, may incr. by 600 mg/day qwk

Bipolar disorder

• 600-1200 mg PO bid
• Start: 300 mg PO bid, incr. by 300 mg/day q3 days or by 600 mg/day qwk

Pediatric Dosing

Partial seizures

adjunct therapy

• 2-3 yo
  • Dose: 60 mg/kg/day PO divided bid; Start: 8-10 mg/kg/day PO divided bid up to 600 mg/day, incr. dose over 2-4wk; Max: 60 mg/kg/day
  • may start 16-20 mg/kg/day PO divided bid in pts <20 kg
• 4-16 yo, 20-29 kg
  • Dose: 600 mg PO bid; Start: 8-10 mg/kg/day PO divided bid up to 600 mg/day, incr. to target dose over 2wk
• 4-16 yo, >39 kg
  • Dose: 900 mg PO bid; Start: 8-10 mg/kg/day PO divided bid up to 600 mg/day, incr. to target dose over 2wk

monotherapy

• 4-16 yo, 20-24 kg
  • Dose: 300-450 mg PO bid; Start: 8-10 mg/kg/day PO divided bid, incr. by 5 mg/kg/day q3 days if initial monotherapy or by up to 10 mg/kg/day qwk if conversion to monotherapy
  • D/C concomitant anticonvulsants over 3-6wk
• 4-16 yo, 25-34 kg
  • Dose: 450-600 mg PO bid; Start: 8-10 mg/kg/day PO divided bid, incr. by 5 mg/kg/day q3 days if initial monotherapy or by up to 10 mg/kg/day qwk if conversion to monotherapy
  • D/C concomitant anticonvulsants over 3-6wk
• 4-16 yo, 35-44 kg
  • Dose: 450-750 mg PO bid; Start: 8-10 mg/kg/day PO divided bid, incr. by 5 mg/kg/day q3 days if initial monotherapy or by up to 10 mg/kg/day qwk if conversion to monotherapy
  • D/C concomitant anticonvulsants over 3-6wk
• 4-16 yo, 45-49 kg
  • Dose: 600-750 mg PO bid; Start: 8-10 mg/kg/day PO divided bid, incr. by 5 mg/kg/day q3 days if initial monotherapy or by up to 10 mg/kg/day qwk if conversion to monotherapy
  • D/C concomitant anticonvulsants over 3-6wk
• 4-16 yo, 50-59 kg
  • Dose: 600-900 mg PO bid; Start: 8-10 mg/kg/day PO divided bid, incr. by 5 mg/kg/day q3 days if initial monotherapy or by up to 10 mg/kg/day qwk if conversion to monotherapy
  • D/C concomitant anticonvulsants over 3-6wk
• 4-16 yo, 60-69 kg
  • Dose: 600-1050 mg PO bid; Start: 8-10 mg/kg/day PO divided bid, incr. by 5 mg/kg/day q3 days if initial monotherapy or by up to 10 mg/kg/day qwk if conversion to monotherapy
  • D/C concomitant anticonvulsants over 3-6wk
• 4-16 yo, >70 kg
  • Dose: 750-1050 mg PO bid; Start: 8-10 mg/kg/day PO divided bid, incr. by 5 mg/kg/day q3 days if initial monotherapy or by up to 10 mg/kg/day qwk if conversion to monotherapy
  • D/C concomitant anticonvulsants over 3-6wk

Special Populations

• Pregnancy Rating: C
• Lactation risk: safety unknown

Renal Dosing

• Adult: CrCl <30: start 150 mg bid; HD/PD: no supplement; Info: titrate dose slowly until response
• Pediatric: CrCl <30: decr. start dose 50%, max start dose 300 mg/24h; HD/PD: no supplement; Info: titrate dose slowly until response

Hepatic Dosing

• Adult: mild-mod impairment: no adjustment; severe impairment: not defined
• Pediatric: mild-mod impairment: no adjustment; severe impairment: not defined

Contraindications

• Allergy to class/drug
• HLA-B*1502 allele (tx-naive pts)
• avoid abrupt withdrawal
• caution if hypersens. to carbamazepine
• caution in elderly pts
• caution in pregnancy
• caution if hyponatremia
• caution if renal impairment
• caution if depression or hx

Adverse Reactions

Serious

• hyponatremia
• anaphylaxis
• angioedema
• drug rxn w/ eosinophilia and systemic sx
• Stevens-Johnson syndrome
• toxic epidermal necrolysis
• erythema multiforme
• acute generalized exanthematous pustulosis
• suicidality
• leukopenia
• thrombocytopenia
• pancytopenia
• agranulocytosis
• aplastic anemia
• pancreatitis
• withdrawal seizures if abrupt D/C
• withdrawal sx if abrupt D/C

Common

• dizziness
• headache
• nausea/vomiting
• somnolence
• diplopia
• balance disorder
• fatigue/asthenia
• tremor
• hyponatremia
• visual disturbance
• nystagmus
• ataxia
• abnormal gait
• abdominal pain
• dyspepsia
• gastritis
• diarrhea
• constipation
• cognitive dysfxn
• impaired concentration
• confusion
• URI sx
• rash
• nervousness
• insomnia
• acne
• photosensitivity

Pharmacology

• Half-life: 2h (parent drug), 7-11h (parent drug, ER form), 9h (metabolite)
• Metabolism: liver; CYP450: 2C19 inhibitor; 3A4/5 inducer; Info: active metabolite
• Excretion: urine 95% (<1% unchanged), feces <4%

Mechanism of Action

blocks voltage-sensitive Na channels, stabilizes neural membranes, inhibits repetitive firing, and decr. synaptic impulse propagation

References

epocrates