In the United States, Trileptal was approved by the Food and Drug Administration (FDA) in 2000 for the treatment of partial seizures. In studies, Trileptal improved control of partial seizures both by itself (monotherapy, for adults) and in combination with other seizure medicines (adjunctive therapy, for adults and children as young as 4 years of age). Trileptal was more recently approved as monotherapy for children 4 and above.

As the generic name of Trileptal (oxcarbazepine) suggests, Trileptal is related to carbamazepine (Tegretol, Carbatrol) and appears to be similarly effective for controlling complex partial seizures and primary and secondarily generalized tonic-clonic seizures. It seems to cause fewer unwanted side effects in many (but not all) patients.

Oxcarbazepine is not effective against absence or myoclonic seizures.