Olanzapine in treatment-resistant bipolar disorder

Background: We evaluated the response to olanzapine in 14 consecutive patients with bipolar I disorder who were inadequately responsive to standard psychotropic agents. Methods: Fourteen patients with bipolar I disorder by DSM-IV criteria experiencing persistent affective symptoms inadequately responsive to at least one standard mood stabilizer were treated with open-label olanzapine by one of the authors. Response was assessed with the Clinical Global Impression Scale modified for use in bipolar disorder (CGI-BP). Results: The 14 patients received olanzapine at a mean (SD dosage of 14.1±7.2 (range 5–30) mg/day for a mean±SD of 101.4+56.3 (range 30–217) days of treatment. Of the 14 patients, 8 (57%) displayed much or very much overall improvement in their illness. In general, olanzapine was well tolerated. The most common side effects were sedation, tremor, dry mouth, and appetite stimulation with weight gain. Limitations: Data were obtained nonblindly and without a randomized control group, and olanzapine was added to ongoing psychotropic regimens. Conclusion: Olanzapine may have antimanic and mood-stabilizing effects in some patients with bipolar disorder, and is generally well tolerated. Controlled studies of olanzapine in bipolar disorder appear warranted.