Spotlight on olanzapine/fluoxetine in acute bipolar depression

Olanzapine/fluoxetine (Symbyax) is an oral once-daily fixed-dose combination of the atypical antipsychotic olanzapine and the SSRI fluoxetine that is approved in the US for the treatment of depressive episodes associated with bipolar disorder in adults. Combination therapy with olanzapine plus fluoxetine is effective in the treatment of patients with acute bipolar depression. The combination improves depressive symptoms and symptom severity in this patient population, with an efficacy greater than that of olanzapine alone or lamotrigine. Furthermore, olanzapine plus fluoxetine is generally well tolerated. Although associated with weight gain and potential elevations in glucose, lipid and prolactin levels, the combination does not increase the risk of treatment-emergent mania. Additional placebo- and active comparator-controlled studies are required in order to confirm the efficacy of olanzapine/fluoxetine in the treatment of bipolar depression and to definitively position olanzapine/fluoxetine with respect to other agents. In the meantime, fixed-dose olanzapine/fluoxetine offers an effective and generally well tolerated first-line option for the treatment of acute bipolar depression.