Objective:Episodes of depression are the most frequent cause of disability among patients with bipolar disorder. Bupropion has been suggested for the treatment of bipolar depression because of its efficacy and a probably lower risk of inducing switches to mania. This study compared the efficacy of quetiapine and bupropion as add-on therapy to ongoing treatment with mood stabilizer in patients with bipolar depression.
Methods:The patients with DSM-IV defined bipolar I/II depression were randomized to receive escalating doses of either quetiapine (300-600mg/day) or bupropion SR (150-300 mg/day) for 8 weeks. Twenty-three patients openly received quetiapine; Twenty-five patients received bupropion SR adjunctive to either lithium or divalproex. The Hamilton Depression Rating Scale(HDRS-21),Clinical Global Impressions for Bipolar Disorder(CGI-BP),Young Mania Rating Scale (YMRS)were assessed.
Results:A significant reduction in depressive symptoms was observed from baseline to endpoint following quetiapine and bupropion SR treatment, according to a > or = 50% reduction in the HDRS-21. Total mean HDRS-21 scores significantly decreased from baseline to endpoint in both groups(p<0.01).Differences between the quetiapine-treated group and the bupropion SR-treated group were not significant at 8 weeks(p>0.05).Adjunctive quetiapine or bupropion SR resulted in significant improvements in CGI-BP depression ratings. Both quetiapine and bupropion SR were generally well tolerated. There were no cases of affective switch in either arm.
Conclusions:These data suggest that adjunctive administration of either quetiapine or bupropion SR may reduce depressive symptom severity in bipolar depression. As this was an observational study, the antidepressant effect and tolerability profile of these compounds requires validation via double-blind placebo controlled investigations.