[How is oxcarbazepine different from carbamazpine?]

Oxcarbazepine (OXC, trade names Timox, Trileptal is a new antiepileptic drug (AED) for treatment of mono- and adjunctive therapy of partial seizures with or without secondary generalization for adults and children older than 6 years of age. Although OXC was developed through structural variation of carbamazepine in order to avoid side effects from metabolites, significant differences have emerged between the two drugs. The mechanism of action mainly involves blockade of sodium currents but differs from CBZ by modulating different types of calcium channels. In contrast to CBZ, which is oxidized by the cytochrome P-450 system, OXC undergoes reductive metabolism at its ketomoiety to form MHD, which is glucuronidated and excreted in the urine. Involvement of the hepatic cytochrome P450-dependent enzymes in the metabolism of OXC is minimal. This allows for better combining of OXC with other AEDs such as valproate. In postmarketing experience of over 800,000 patient-years, OXC also showed an advantageous risk-benefit ratio. Oxcarbazepine should be preferred over CBZ and other older AEDs due to its very good efficacy and better side effect profile in children, adolescents, and adults with partial seizures.