Mania Induced by Risperidone: Dose Related?

Sir: Risperidone is a serotonin-2/dopamine-2 (5-HT₂/D₂) receptor antagonist that has demonstrated efficacy in the treatment of schizophrenia. It has also been suggested to possess acute antimanic effects in some patients. Other preliminary data, however, indicate that risperidone may initiate or exacerbate manic symptoms owing to its putative antidepressant activity.