A recent trial examined the impact of augmenting antidepressant treatment with risperidone. Participants had not shown a treatment response after taking an antidepressant for at least five weeks, and were then randomly assigned to receive either risperidone or placebo aug- mentation along with the same dose of their antidepressant. Risperidone was flex- ibly dosed between 0.5 mg and 3 mg based on clinical response and side effects. At the end of the four-week trial, the remission rate on the Montgomery- Asberg Depression Rating Scale (MADRS) was significantly higher among risperi- done augmentation patients than placebo augmentation patients (52% vs. 24%). Response rates on the MADRS were also significantly higher for patients taking risperidone (55% vs. 33%). However, there was no significant advantage for risperidone on Clinical Global Impressions scores or response on the Hamilton Depression Rating Scale (HAM- D). Initially, patients on risperidone showed more change on the MADRS, but this advantage became smaller and statisti- cally nonsignificant by the end of the study. Patients on risperidone gained sig- nificantly more weight than those taking placebo (4.3 pounds vs. 0.3 pounds). No EPS symptoms were reported (Keitner GI et al., J Psychiatr Res 2009;43:205-214).

TCPR’s Take: The results of this study imply that risperidone might be a useful short term strategy to “kick-start” a response in patients who have not responded to the antidepressant alone. Short term use would potentially prevent the more extreme side effects of risperidone, although we do not know what the risk of relapse would be after discontinuation.