# Trileptal ### (oxcarbazepine) **[Trileptal](https://wiki.joshnp.com/books/drug-library/page/trileptal)** (oxcarbazepine); not controlled
[**Full Prescribing Information**](https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=33af9350-95f3-384e-e054-00144ff88e88&type=display)[**DailyMed Drug Information**](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=33af9350-95f3-384e-e054-00144ff88e88)
--- ### **Summary** Trileptal is a sodium channel blocking antiepileptic, supplied as tablets and oral suspension, approved only for partial seizures: monotherapy from 4 years, adjunctive from 2 years. It carries no psychiatric indication at any age, so use for aggression, mood dysregulation or impulse control is entirely off-label. Its defining safety issue is hyponatremia, common enough to require scheduled sodium checks. Not controlled; brand and generic. --- ### **Forms & Strengths** - **Tablets:** 150 mg, 300 mg, 600 mg - **Oral suspension:** 300 mg/5 mL - **Extended-release tablets:** 150 mg, 300 mg, 600 mg --- ### **Dosing** - **Age:** - Partial seizures, monotherapy: 4 y/o and older - Partial seizures, adjunctive: 2 y/o and older - Psychiatric and behavioural use: no approved age; entirely off-label - **Onset:** 2 to 4 weeks, the time titration takes to reach target - **Duration:** continuous with twice-daily dosing - **Initial Dose:** - Pediatric monotherapy, 4 to 16 y/o: 8 to 10 mg/kg/day in two divided doses - Pediatric adjunctive, 2 to 16 y/o: 8 to 10 mg/kg/day divided, generally not above 600 mg/day - Under 20 kg: 16 to 20 mg/kg/day may be considered - Adults, all uses: 600 mg/day in two divided doses - **Titration:** - Pediatric monotherapy initiation: 5 mg/kg/day every 3 days - Pediatric conversion to monotherapy: up to 10 mg/kg/day weekly - Pediatric adjunctive: reach target over 2 weeks, or 2 to 4 weeks under 4 y/o - Adults: up to 600 mg/day weekly; 300 mg/day every third day for monotherapy - **Max Dose:** - Pediatric adjunctive, 2 to under 4 y/o: 60 mg/kg/day - Adjunctive 4 to 16 y/o: 900 mg/day at 20 to 29 kg, 1200 mg/day at 29.1 to 39 kg, 1800 mg/day above 39 kg - Monotherapy maintenance: 600 to 900 mg/day at 20 kg, up to 1500 to 2100 mg/day at 70 kg - Adults: 2400 mg/day, which most patients cannot tolerate - **Considerations:** All dosing is twice daily. Halve the starting dose to 300 mg/day and titrate slowly if creatinine clearance is under 30 mL/min; no adjustment for mild to moderate hepatic impairment. --- ### **Pharmacology** - **Mechanism:** Blocks voltage-gated sodium channels, stabilising hyperexcited membranes; no demonstrated interaction with brain neurotransmitter or modulator receptors - **Delivery / Release:** immediate-release, completely absorbed, median Tmax 4.5 hours; with or without food - **Metabolism:** prodrug converted to the active 10-monohydroxy derivative (MHD); half-life 2 hours parent, 9 hours MHD, 19 hours if creatinine clearance is under 30 mL/min - **Pharmacogenomics:** HLA-B\*1502 carriers risk Stevens-Johnson syndrome and toxic epidermal necrolysis. Test before starting in at-risk ancestry; avoid unless benefit clearly outweighs risk. - **Class Positioning:** like carbamazepine but with much less enzyme induction; hyponatremia is more frequent, not less. Adjunct to an ADHD regimen ([Concerta](https://wiki.joshnp.com/link/11), [Strattera](https://wiki.joshnp.com/link/4), [Qelbree](https://wiki.joshnp.com/link/36)), never a replacement. --- ### **Indications** - **Partial Seizures, monotherapy** (ICD-10: G40.1, G40.2): patients 4 y/o and older, and adults - **Partial Seizures, adjunctive therapy** (ICD-10: G40.1, G40.2): patients 2 y/o and older, and adults - No other approved indication exists, psychiatric or otherwise, at any age. --- ### **Off-Label Uses** - **Aggression, irritability and mood dysregulation** (ICD-10: F90.x, F91.x): limited data. Risperidone ([Risperdal](https://wiki.joshnp.com/link/96)) has moderate graded evidence here; oxcarbazepine has none. (AHRQ 2017) - **Where the evidence does not support use:** - **Pediatric bipolar disorder** (ICD-10: F31.x): insufficient; the carbamazepine analogy is pharmacological, not evidential. - **Neuropathic pain, trigeminal neuralgia** (ICD-10: G50.0, M79.2): insufficient; no pain indication at any age. - **Generalized seizures** (ICD-10: G40.3): insufficient and potentially harmful; can worsen some generalized epilepsies. --- ### **Contraindications & Warnings** - **Class warning, suicidal behaviour and ideation:** antiepileptics roughly double the risk (adjusted RR 1.8, 95% CI 1.2 to 2.7), from week one, in every indication. - **Contraindicated:** known hypersensitivity to oxcarbazepine or any component. - **Use with caution:** - Prior carbamazepine hypersensitivity: 25% to 30% cross-react. Ask directly. - Ancestry in a high HLA-B\*1502 frequency population, for Stevens-Johnson syndrome and toxic epidermal necrolysis risk. - Any other sodium-lowering drug: thiazides, SNRIs, drugs causing inappropriate ADH secretion. - Creatinine clearance under 30 mL/min: halve the starting dose; MHD half-life roughly doubles. - Hormonal contraception in an adolescent, because oxcarbazepine reduces its effectiveness. - Pregnancy or possible pregnancy, because oxcarbazepine is likely a human teratogen. - **Screen before starting:** - Baseline serum sodium; a later result cannot be interpreted without it. - Prior reaction to carbamazepine, asked as a direct question. - Ancestry, to decide whether HLA-B\*1502 testing is indicated first. - Renal function; the medication list for sodium-lowering drugs and hormonal contraception. - Baseline mood and any history of suicidal ideation. --- ### **Drug Interactions** - **Hormonal contraceptives** (oral, patch, ring): effectiveness is reduced. Arrange an alternative or added method before the first dose. - **Other antiepileptics** (carbamazepine, phenytoin, phenobarbital): mutual changes in exposure above 1200 mg/day. Check their levels through titration and at any dose change. - **Calcium antagonists** (felodipine, verapamil): exposure is altered. Recheck blood pressure after any change. - **Other sodium-lowering drugs** (thiazides, SSRIs, SNRIs, desmopressin, carbamazepine): additive hyponatremia. Check sodium 2 to 4 weeks after starting and at any dose change. - **Laboratory tests:** T4 falls without T3 or TSH change. Read an isolated low T4 as a drug effect, not hypothyroidism. --- ### **Administration** - Give twice daily at roughly 12-hour intervals. The extended-release oxcarbazepine product is a separate NDA and must not be substituted milligram for milligram. - May be taken with or without food. - Use the oral suspension for weight-based pediatric dosing rather than splitting tablets. - The suspension is 60 mg/mL: divide the milligram dose by 60 for millilitres. - Shake the suspension; measure with a calibrated oral syringe, never a kitchen spoon. - Do not stop abruptly. See Discontinuation & Taper. --- ### **Side Effects** - **Common** (at least 5%, above placebo): dizziness, somnolence, diplopia, fatigue, nausea, vomiting, ataxia, abnormal vision, abdominal pain, tremor, dyspepsia, abnormal gait - **Serious:** - Hyponatremia: sodium below 125 mmol/L in 2.5% of treated patients, usually asymptomatic. Reduce the dose or stop. - Anaphylaxis and angioedema of the larynx, glottis, lips or eyelids: stop and never rechallenge. - Stevens-Johnson syndrome and toxic epidermal necrolysis, median onset 19 days. Stop for any rash. - DRESS: fever, rash or lymphadenopathy with organ involvement. Discontinue unless another cause is established. - Dose-related psychomotor slowing, impaired concentration, speech problems, ataxia and gait disturbance. - Pancytopenia, agranulocytosis and leukopenia, rare: consider discontinuation. --- ### **Monitoring & Labs** - **Serum sodium:** baseline, 2 to 4 weeks after starting, after every dose increase, at 3 months, then at least every 6 months; also 2 to 4 weeks after adding any sodium-lowering drug. - **Serum sodium, unscheduled:** for nausea, malaise, headache, lethargy, confusion, obtundation, or rising seizure frequency. Act before 125 mmol/L. - **Suicidality and mood:** at 1 week, 1 month, every dose change, and each routine visit thereafter. - **Skin:** ask about rash at every visit for the first 3 months; the family reports any rash the same day. - **Cognitive and motor function:** ask family and school about concentration, sleepiness and falls at each dose increase and every 6 months. - **Contraception review:** every visit, in any adolescent who could become pregnant. --- ### **Discontinuation & Taper** - **Withdraw gradually**, per the label, to minimise increased seizure frequency. This holds even for off-label behavioural use. - Converting to another antiepileptic: withdraw over 3 to 6 weeks while the replacement reaches target over 2 to 4 weeks. - Stop permanently, no rechallenge, for anaphylaxis, angioedema or any serious dermatological reaction. - Discontinue for DRESS unless an alternative cause is established. - Reduce or stop for clinically significant hyponatremia; sodium normalises within a few days. - Drug holidays are not appropriate for either use. --- ### **Pregnancy & Lactation** - **Pregnancy:** No adequate controlled studies; the label states oxcarbazepine is likely a human teratogen. Use only if benefit justifies risk. - **Pregnancy, dosing:** plasma MHD falls through pregnancy and returns after delivery; monitor seizure control across pregnancy and postpartum. - **Lactation:** milk-to-plasma ratio 0.5; levels low, adverse effects not expected beyond 2 months. Monitor infant drowsiness, weight gain, milestones. (LactMed 2024) - **Exposure Registry:** North American Antiepileptic Drug Pregnancy Registry, 1-888-233-2334; the patient enrolls herself. --- ### **Counseling Points** - **Counsel the family on:** - This being a seizure medicine; behavioural use is off-label, with no approved dose ladder. - The sodium blood test schedule, done even when the child feels well; most affected children have no symptoms. - Reporting any rash the same day; name blistering, peeling and mouth or eye sores. - Sleepiness, unsteadiness and double vision being dose-related; report after an increase. - Never stopping suddenly, even if it seems to be doing nothing: that can trigger seizures. - For an adolescent who could become pregnant: less reliable hormonal birth control, likely fetal harm. - **Advise them to call for:** - Blistering or peeling skin, or mouth, eye or genital sores, immediately. - Swelling of the lips, tongue, eyelids or throat, or trouble breathing. - Fever with swollen glands, with or without rash. - Headache with unusual sleepiness, confusion, unsteadiness, or more frequent seizures. - New or worsening talk of self-harm, or a sudden mood change. - Unusual bruising, bleeding, or repeated infections. --- ### **References** 1. DailyMed. Trileptal (oxcarbazepine) tablets prescribing information. 2026. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=33af9350-95f3-384e-e054-00144ff88e88 2. LactMed. Oxcarbazepine. Drugs and Lactation Database, National Institute of Child Health and Human Development. 2024. https://www.ncbi.nlm.nih.gov/books/NBK501243/ 3. AHRQ. First- and second-generation antipsychotics in children and young adults: systematic review update. Comparative Effectiveness Review No. 184. 2017. https://www.ncbi.nlm.nih.gov/books/NBK442344/ 4. FDA. National Drug Code Directory, openFDA. Queried by generic name oxcarbazepine. 2026. https://api.fda.gov/drug/ndc.json?search=generic\_name:%22oxcarbazepine%22&limit=1000