New treatments for bipolar disorder: the role of atypical neuroleptic agents.

Atypical neuroleptic agents are an excellent, safer, and more effective alternative to the widespread practice of maintenance adjunctive treatment with traditional neuroleptic agents in patients with bipolar disorder. Currently, a number of prospective studies are available with clozapine, risperidone, olanzapine, and quetiapine in the treatment of bipolar disorder. Most are short-term studies, although longer-term data are becoming available. Four double-blind studies of acute mania have been conducted with risperidone and olanzapine, leading to recent Food and Drug Administration approval for olanzapine in the indication of acute mania. Given the limited longer-term data, and the evidence for mostly adjunctive benefits with these agents, it seems unlikely that these agents will prove to be primary mood stabilizers in their own right. Nonetheless, they serve an important role as adjunctive treatments along with standard mood stabilizers in the rational polypharmacy of bipolar disorder. To date, differences in efficacy have not been established. However, differences in the side effect of weight gain may be even more relevant in bipolar disorder than in schizophrenia due to the need to use standard mood stabilizers that often potentiate such weight gain.