Adult: As monotherapy or adjunctive therapy: Initially, 600 mg daily in 2 divided doses, may increase if necessary in max increments of 600 mg daily at wkly intervals. Maintenance dose: 600-1,200 mg daily or up to 2,400 mg daily in adjunctive therapy or in refractory patients switched from other antiepileptics. Child: ≥6 yr 8-10 mg/kg daily in 2 divided doses, may increase if necessary in increments of 10 mg/kg daily at wkly intervals. Maintenance dose: 30 mg/kg daily in adjunctive therapy. Max: 46 mg/kg/day.
Special Patient Group
Human leukocyte antigen B (HLA-B) variant allele HLA-B*15:02 is associated with the development of serious cutaneous adverse reactions [e.g. Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN)] to aromatic anticonvulsants (e.g. carbamazepine, lamotrigine, phenytoin, phenobarbital). The prevalence of this allele has been estimated in 6.9% of East Asians, 5.5% of Oceanians, 4.6% of South/Central Asians, <1% of Japanese, <2.5% of Koreans, rare in Africans, and <1% of African Americans, Middle Easterners, Caucasians, Hispanic/South Americans.
Patients who are positive to HLA-B*15:02 allele may have greater risk of developing SJS/TEN when treated with oxcarbazepine. CPIC strongly recommends avoiding use of oxcarbazepine, and cautiously consider alternative aromatic anticonvulsant therapy in these patients. Consider genetic screening prior to initiation of therapy.
The latency period for SJS/TEN is short with continuous dosing of approx 4-28 days, and ADR usually occur within 3 months of use. Therefore, if patient previously used oxcarbazepine consistently for more than 3 months without incidence of SJS/TEN, cautiously consider use of oxcarbazepine in the future. However, tolerance to oxcarbazepine is not indicative of tolerance to other aromatic anticonvulsants.
Initially, 300 mg daily, increased at wkly intervals or longer.
May be taken with or without food.
Patient carrying the HLA-B*1502 allele. Avoid abrupt withdrawal. Severe renal and hepatic impairment. Pregnancy.
Monitor seizure frequency, serum Na, symptoms of CNS depression, hypersensitivity reactions, serum levels of concomitant antiepileptic drugs during titration; periodic thyroid function test and CBC.
Symptoms: Somnolence, dizziness, nausea, vomiting, hyperkinesia, hyponatraemia, ataxia and nystagmus. Management: Symptomatic and supportive treatment. Employ gastric lavage and/or administer activated charcoal to facilitate removal of medicinal product.
May increase plasma concentrations of other anticonvulsants (e.g. phenobarbital, phenytoin). May decrease plasma concentrations of OC and Ca channel blockers. Decreased plasma concentrations w/ potent inducers of CYP isoenzymes (e.g. carbamazepine, phenytoin, phenobarbital).
Additive sedative effect w/ alcohol.
May depress serum T4 w/o affecting T3 or TSH.
Description: Oxcarbazepine and monohydroxy derivative (MHD) block voltage-sensitive Na channels, stabilising hyperexcited neuronal membranes, inhibiting repetitive firing, and decreasing the propagation of synaptic impulses. These actions are believed to prevent the spread of seizures. Oxcarbazepine and MHD also increase K conductance and modulate the activity of high-voltage activated Ca channels. Pharmacokinetics: Absorption: Completely absorbed from the GI tract. Time to peak plasma concentration: 4.5 hr (tab); 6 hr (oral susp). Distribution: Widely distributed throughout the body. Crosses the placenta and enters breast milk. Plasma protein binding: Approx 40%, mainly albumin. Metabolism: Hepatic; rapidly and extensively metabolised to the principal metabolite, 10, 11-dihydro-10-hydroxy-carbamazepine (MHD). Excretion: Via urine, mainly as metabolites, and <1% as unchanged drug. Plasma half-life: Approx 2 hr (oxcarbazepine); approx 9 hr (monohydroxy metabolite).
N03AF02 - oxcarbazepine ; Belongs to the class of carboxamide derivatives antiepileptic.
Anon. Oxcarbazepine. AHFS Clinical Drug Information [online]. Bethesda, MD. American Society of Health-System Pharmacists, Inc. https://www.ahfscdi.com. Accessed 20/09/2018.Anon. Oxcarbazepine. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 20/09/2018.Buckingham R (ed). Oxcarbazepine. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 20/09/2018.Buckingham R (ed). Oxcarbazepine. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 28/01/2015.Clinical Annotation for HLA-B*15:02:01 related to Oxcarbazepine. Pharmacogenomics Knowledgebase (PharmGKB). https://www.pharmgkb.org/ . Accessed 20/09/2018.Joint Formulary Committee. Oxcarbazepine. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 20/09/2018.McEvoy GK, Snow EK, Miller J et al (eds). Oxcarbazepine . AHFS Drug Information (AHFS DI) [online]. American Society of Health-System Pharmacists (ASHP). https://www.medicinescomplete.com. Accessed 28/01/2015.Oxcarbazepine Tablet, Film-coated (Jubilant Cadista Pharmaceuticals, Inc). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 28/01/2015.Trileptal Tablets and Oral Suspension. U.S. FDA. https://www.fda.gov/. Accessed 28/01/2015.