Carbamazepine and Valproate in the Maintenance Treatment of Bipolar Disorder

Background: Carbamazepine and valproate are used in the treatment of acute bipolar mania and as maintenance treatments for bipolar disorder. We reviewed the available data from randomizedclinical trials of these agents in bipolar disorder to assess their efficacy and tolerability in the maintenancephase of illness management. Data Sources: We conducted a MEDLINE search augmented by a manual search of bibliographies, textbooks, and abstracts from recent scientific meetings to identify studies of carbamazepine and valproate in the maintenance treatment of bipolar disorder. DataSynthesis: Although a paucity of data exists from randomized, placebo-controlled trials, carbamazepineand valproate appear to prevent relapse as monotherapy in patients with bipolar disorder. Preliminaryevidence of predictors of response to each respective agent has been identified. Combinationsof carbamazepine and lithium and of valproate and olanzapine may have greater efficacy than monotherapy. Conclusion: Although carbamazepine and valproate have been less well studied in maintenance treatment than lithium, each agent appears to have efficacy in this phase of illness management.However, for many patients, combination therapy may provide better long-term preventionof illness relapse and recurrence.