Venlafaxine monotherapy in women with bipolar II and unipolar major depression

Women with bipolar (BP) disorder have more depressive episodes and drug-induced manic switches compared to men. Current guidelines suggest treating BP type I and type II major depressive episode (MDE) with both a mood-stabilizer and antidepressant. In a post hoc analysis, we examined the safety and efficacy of venlafaxine monotherapy in women with BP II MDE.

15 women with BP II MDE (mean+/-SD age: 37+/-12 years) were compared to 17 women with unipolar (UP) MDE (41+/-12 years). Patients were randomized to double-blind treatment with once versus twice daily venlafaxine up to 225 mg for 6 weeks. Efficacy was measured using the HAM-D(21), MADRS and CGI scales. Drug-induced manic switch episodes characterized by agitation, irritability, euphoria or mood lability were assessed at each visit.

No episodes of drug-induced hypomania or rapid cycling were observed during 6 weeks of venlafaxine monotherapy. Similar efficacy was observed in BP and UP depressed women (p=ns).

This study was retrospective in nature and limited in patient number. Only BP II women were included in this study, and it is possible that efficacy and the manic switch rate might have differed if BP I women were included.

Short-term venlafaxine monotherapy may be a safe and effective antidepressant treatment in women with BP II MDE.