Perspectives on the use of anticonvulsants in the treatment of bipolar disorder.

The authors reviewed the available literature on the efficacy of carbamazepine, valproate, and other newer anticonvulsants for the treatment of bipolar disorder. A comprehensive Medline search was conducted, and all uncontrolled and controlled reports on anticonvulsants used for the treatment of bipolar patients were identified. Carbamazepine and valproate have been shown to be effective in the acute treatment of bipolar disorder, and are the first-choice treatments for lithium-refractory patients. While the efficacy of these drugs in the acute treatment of the illness has been satisfactorily documented, double-blind randomized studies are still necessary to evaluate the long-term effectiveness of both anticonvulsants. Patients on a mixed state and rapid cyclers seem to respond better to valproate and carbamazepine than to lithium. The preliminary data evaluating the efficacy of newer anticonvulsants, such as gabapentin, lamotrigine, and topiramate in bipolar patients is still limited, but some of the available findings are promising, and these new agents may represent appropriate third choices for refractory bipolar individuals. Double-blind, controlled studies with the newer anticonvulsants are still largely unavailable, and it will be necessary to evaluate their acute and prophylactic mood-stabilizing effects. The prospects for future therapeutic advances in this area are also discussed.