Historical review of carbamazepine for the treatment of bipolar disorder.

The management of bipolar disorder has seen significant evolution in terms of the number of treatment options now approved for both the acutely manic phase and the maintenance stages of the illness. In addition, new formulations of traditional agents are available for clinicians to use in their treatment approach. One such example is carbamazepine, which has approval by the United States Food and Drug Administration for the treatment of acute and mixed mania in an extended-release formulation that uses a three-bead delivery system. Although the parent compound has been available for decades, its approval for bipolar disorder is recent despite numerous clinical trials that have supported its use in both the acute and maintenance phases of bipolar disorder. Advantages of the new formulation include less fluctuation in plasma concentration and, in general, improved tolerability. However, issues remain with regard to cytochrome P450 drug-related interactions and the need for therapeutic drug monitoring (e.g., drug concentrations, epoxide metabolite concentrations, hematology, and liver function tests) as part of the treatment and monitoring process. We review the current body of literature describing the use of carbamazepine in bipolar disorder during both the acute and maintenance phases of the disorder, including trials of both monotherapy and combination therapy, as well as findings from trials that included patients with rapid cycling and mixed episodes.