Few double-blind trials have examined the efficacy of a combination of a mood stabiliser and an atypical antipsychotic in acute mania.

To determine the efficacy of risperidone in combination with a mood stabiliser in acute mania.

Patients taking a mood stabiliser were randomised to 3 weeks' treatment with risperidone (n=75) or placebo (n=76).

Young Mania Rating Scale (YMRS) scores improved rapidly with significantly greater reductions at week 1 in the risperidone group compared with the placebo group. At end-point YMRS scores decreased by 14.5 and 10.3 points in the risperidone and placebo groups, respectively. Significant improvements v. placebo (P < 0.05) were noted in the risperidone group on several other clinically meaningful measures. Additionally, a post hoc analysis excluding carbamazepine-treated patients (plasma concentrations of risperidone active moiety were 40% lower in this group) revealed significantly greater reductions (P=0.047) in YMRS scores in the risperidone group than in the placebo group. Incidence of adverse events was similar in both groups.

Risperidone is superior to placebo when used in combination with lithium or divalproex in acute mania.