Trileptal (oxcarbazepine) is a second-generation antiepileptic drug (AED) indicated for the treatment of partial seizures in adults and children as young as 2 years of age. As a keto-analogue of carbamazepine, it offers a refined mechanism of action with a potentially improved tolerability profile. Its active metabolite, 10-monohydroxy derivative (MHD), primarily exerts therapeutic effects through voltage-sensitive sodium channel modulation, stabilizing hyperexcited neuronal membranes and inhibiting repetitive neuronal firing. Clinicians value Trileptal for its efficacy in monotherapy and adjunctive therapy, supported by a robust clinical trial history demonstrating significant reductions in seizure frequency.

Features

• Active ingredient: Oxcarbazepine
• Available formulations: Film-coated tablets (150mg, 300mg, 600mg) and oral suspension (60mg/mL)
• Mechanism: Voltage-gated sodium channel blockade
• Half-life: Approximately 1–2.5 hours for oxcarbazepine; 9 hours for its active metabolite MHD
• Metabolism: Hepatic, via cytosolic arylketone reductase
• Excretion: Primarily renal (95% as metabolites, <1% unchanged)

Benefits

• Provides effective reduction in partial seizure frequency with or without secondary generalization
• Lower risk of severe dermatological reactions and autoinduction compared to first-generation AEDs
• Linear pharmacokinetics allow for predictable dosing adjustments
• Suitable for pediatric populations down to 2 years of age with weight-based dosing
• May be administered twice daily, supporting adherence
• Available in multiple formulations for dosing flexibility across patient needs

Common use

Trileptal is primarily prescribed for the management of partial-onset seizures, which may present with simple partial, complex partial, or secondarily generalized tonic-clonic manifestations. It is approved for use as both monotherapy and adjunctive therapy in adults and pediatric patients. Off-label applications may include the treatment of bipolar disorder, trigeminal neuralgia, and neuropathic pain, though evidence supporting these uses varies. Clinical decisions should be guided by comprehensive neurological assessment and individual patient profiles.

Dosage and direction

Initiate therapy with a low dose, titrating upward based on clinical response and tolerability. For adults beginning monotherapy, start with 600mg/day divided into two doses; increase by 300mg/day every third day to a target maintenance dose of 1200mg/day. Maximum recommended dose is 2400mg/day. For adjunctive therapy in adults, initiate at 600mg/day divided bid; may increase by 600mg/day at weekly intervals to a maximum of 2400mg/day.

Pediatric dosing is weight-based: initiate at 8–10mg/kg/day, not to exceed 600mg/day, divided bid. Titrate to target maintenance dose over two weeks. For children 20–29kg: 900mg/day; 29.1–39kg: 1200mg/day; >39kg: 1800mg/day. Administer with or without food. Oral suspension should be shaken well and may be mixed with water immediately before ingestion. Use provided dosing syringe for accuracy.

Precautions

Hyponatremia (serum sodium <125 mmol/L) may occur, particularly in the elderly and those on concomitant medications that lower sodium; monitor serum sodium levels during initial treatment and periodically thereafter. Caution in patients with renal impairment (CrCl <30 mL/min); dose adjustment recommended. Use with care in patients with hepatic impairment due to potential for reduced metabolism. May cause dizziness and somnolence; advise patients regarding activities requiring mental alertness. Multiorgan hypersensitivity reactions (e.g., DRESS) have been reported; discontinue if suspected. Suicidal ideation and behavior have been observed with AEDs; monitor for emergence or worsening of depression.

Contraindications

Hypersensitivity to oxcarbazepine, eslicarbazepine acetate, or any component of the formulation. Known hypersensitivity reaction to carbamazepine, as cross-reactivity occurs in up to 25–30% of patients.

Possible side effect

Common (≥5%): Dizziness (23%), somnolence (23%), headache (15%), nausea (15%), vomiting (13%), diplopia (11%), fatigue (11%), ataxia (8%), abnormal vision (7%), tremor (6%).
Serious: Hyponatremia, anaphylactic reactions, Stevens-Johnson syndrome, toxic epidermal necrolysis, agranulocytosis, aplastic anemia, hepatitis, suicidal behavior and ideation, drug reaction with eosinophilia and systemic symptoms (DRESS).

Drug interaction

Strong CYP3A4 inducers (e.g., carbamazepine, phenytoin) may decrease MHD concentrations. May reduce efficacy of hormonal contraceptives; alternative non-hormonal contraception recommended. May increase phenytoin levels; monitor and adjust phenytoin dose as needed. Caution with other CNS depressants (e.g., alcohol, benzodiazepines). May decrease exposure to simvastatin, calcium channel blockers, and certain immunosuppressants.

Missed dose

If a dose is missed, take it as soon as remembered unless it is nearly time for the next dose. Do not double the dose to make up for a missed one. Maintain regular dosing schedule to ensure stable plasma concentrations.

Overdose

Symptoms may include drowsiness, dizziness, nausea, vomiting, hyperkinesia, hyponatremia, ataxia, nystagmus, coma. No specific antidote exists. Provide supportive care, including monitoring of vital signs and electrolyte levels. Consider gastric lavage if presented early. Hemodialysis may be effective due to moderate dialyzability of MHD.

Storage

Store at 25°C (77°F); excursions permitted to 15–30°C (59–86°F). Keep tablets in original container, tightly closed. Oral suspension: store at room temperature; discard 7 weeks after first opening. Keep out of reach of children and pets.

Disclaimer

This information is for educational purposes and does not replace professional medical advice. Always consult a healthcare provider for diagnosis, treatment decisions, and individualized dosing. Do not discontinue therapy abruptly due to risk of increased seizure frequency.

Reviews

“Trileptal has been a cornerstone in my practice for managing partial seizures, particularly in patients who could not tolerate carbamazepine. The predictable pharmacokinetics and lower interaction profile make it a reliable choice.” — Neurologist, 12 years of experience.

“While effective, vigilance for hyponatremia is necessary, especially in elderly patients on polypharmacy. Routine sodium monitoring during titration is non-negotiable in my protocol.” — Clinical Pharmacist, Epilepsy Center.

“Pediatric formulation allows accurate dosing down to very young patients. Saw significant reduction in seizure frequency in my pediatric cohort with manageable side effects.” — Pediatric Neurologist.