Self-induced water intoxication treated with risperidone.

OBJECTIVE To determine whether or not risperidone is efficacious in treating self-induced water intoxication in patients with chronic schizophrenia. METHOD We carried out a prospective 11-month open-label study using risperidone to treat 8 men with chronic schizophrenia and self-induced water intoxication. RESULTS The 8 men were not able to reduce their fluid consumption compared with their baseline intake. Risperidone, however, significantly decreased the Brief Psychiatric Rating Scale (BPRS) scores of this very chronic group. CONCLUSIONS Although risperidone decreased schizophrenic symptoms, it did not have significant efficacy in treating self-induced water intoxication. This study may have implications for the treatment of addictive behaviour.