Oxcarbazepine in the treatment of bipolar and schizoaffective disorders

Oxcarbazepine is an antiepileptic drug that has been approved by the US FDA and is indicated for use as monotherapy or adjunctive therapy in the treatment of partial seizures in adults and children aged over 4 years. The aim of this report is to investigate the results of clinical trials in order to ascertain the efficacy and safety of oxcarbazepine for use in bipolar disorder and schizoaffective disorder. Oxcarbazepine is a keto-congener of carbamazepine with fewer side effects and drug interactions. Orally administrated oxcarbazepine is rapidly and completely absorbed and has a half-life of 9 h. Currently, there is a lack of controlled clinical trials studying the use of oxcarbazepine. In light of controlled and open-label prospective studies, it may be useful for manic symptoms in the treatment of bipolar and schizoaffective patients. Case reports, retrospective and prospective studies suggest that oxcarbazepine might have prophylactic efficacy and long-term benefit for these patients. In addition, owing to its lower propensity for drug interactions and side effects, it may be useful in the treatment of refractory patients with bipolar and schizoaffective disorder. However, most of the trials have relevant methodological shortcomings. The side-effect profile of oxcarbazepine is similar to carbamazepine, but the severity of these effects appears to be slightly less. The symptoms that are most frequently associated with the use of oxcarbazepine are asthenia, headache, dizziness, somnolence, nausea, diplopia and skin rash. Isolated cases of hyponatremic coma have been reported, thus electrolyte abnormalities should be closely monitored. Oxcarbazepine is now a generic drug, but the metabolite licarbazepine and other related compounds, such as eslicarbazepine, are currently being studied under controlled conditions and might become useful therapies for bipolar and schizoaffective disorder in the future.