Objective: To evaluate effects of olanzapine in diverse exacerbations of bipolar disorders.
Methods: Twenty-five evaluable bipolar disorder [14 bipolar I (BPI), 10 bipolar II (BPII) and one bipolar disorder not otherwise specified (BP NOS)] outpatients received open olanzapine (15 adjunctive, 10 monotherapy). Thirteen had elevated (11 syndromal, two subsyndromal) and 12 depressed (four syndromal, eight subsyndromal) mood symptoms of at least mild severity, with Clinical Global Impression-Severity (CGI-S) scores of at least 3. Only one had psychotic symptoms.
Results: With open olanzapine (15 adjunctive, 10 monotherapy), overall symptom severity (CGI-S) as well as mood elevation (Young Mania Rating Scale), depression (Hamilton and Montgomery-Asberg Depression Rating Scales), and anxiety (Hamilton Anxiety Rating Scale), rapidly decreased (significantly by days 2–3). Patients with the greatest baseline severity (CGI-S) had the greatest improvement. Fifteen of 25 (60%) patients responded. Time to consistent response was bimodal, with five early (by 0.5 ± 0.3 weeks) and 10 late (by 7.0 ± 1.9 weeks) responders. Early compared with late responders had 51% lower final olanzapine doses. Olanzapine was generally well tolerated, with sedation and weight gain the most common adverse effects.
Conclusions: Olanzapine was effective in diverse exacerbations of bipolar disorders. The bimodal distribution of time to response and different final doses are consistent with differential mechanisms mediating early compared with late responses. Controlled studies are warranted to further explore these preliminary observations.