Oxcarbazepine in bipolar disorder: a critical review of the literature

Oxcarbazepine (OXC) is a keto-congener of carbamazepine, which has fewer side effects and drug interactions. However, the efficacy of OXC in treating bipolar disorder is not as well established as that of carbamazepine. This article is a systematic literature review of all studies regarding OXC and bipolar disorders, with particular attention to papers published in the last 6 years. Using the terms 'oxcarbazepine and bipolar disorder', 'oxcarbazepine and mania' or 'oxcarbazepine and bipolar depression', a computer-aided search of MEDLINE for the years 2000-2006 has been conducted. Since its introduction as an antiepileptic drug in early 2000, clinical research regarding the potential role of OXC in the treatment of bipolar disorder remains limited. There is a lack of double-blind, placebo-controlled studies. Studies recently published have small samples of patients, with insufficient follow-up periods and other methodological weaknesses. The efficacy of OXC in bipolar disorder has not been widely studied. Some authors recommend using OXC as monotherapy or as add-on therapy in refractory mania, although results are not conclusive. It is unknown whether OXC has efficacy in the maintenance treatment of bipolar disorder. OXC can be particularly useful as an add-on treatment in bipolar disorder patients for whom previous treatments have failed, or in patients who have difficulty tolerating adequate dosages of standard approved treatments.