Risperidone in combination with mood stabilizers: a 10-week continuation phase study in bipolar I disorder.

BACKGROUND: Combination therapy (risperidone and a mood stabilizer) for patients with a history of bipolar disorder (DSM-IV) and hospitalized for treatment of a manic episode was assessed in a 13-week study. METHOD: Subjects received flexible doses of a mood stabilizer (lithium or divalproex) plus placebo, risperidone, or haloperidol in a 3-week double-blind study. They could then enter a 10-week open-label study during which they received risperidone combined with a mood stabilizer. RESULTS: Of the 156 patients enrolled in the 3-week study, 85 entered the 10-week open-label extension, of whom 48 completed 10 weeks of treatment. The mean +/- SE doses of risperidone were 3.8 +/- 0.3 mg/day during the 3-week study and 3.1 +/- 0.2 mg/day during the 10-week study. At double-blind endpoint, mean reductions in Young Mania Rating Scale (YMRS) scores were significantly greater in patients receiving risperidone plus mood stabilizer than in those receiving placebo plus mood stabilizer (-14.3 vs. -8.2, p <.001). Further significant (p <.001) reductions were seen during the 10 weeks of treatment with risperidone plus mood stabilizer. Symptom remission (YMRS score