THE EFFECT OF RISPERIDONE ON SCHEDULE-INDUCED-POLYDIPSIA

The effects of risperidone on the acquisition of schedule-induced poly dipsia in rats were investigated in a chronic dose regime followed by seven days of withdrawal. Risperidone dose-dependently suppressed wate r intake and number of panel pushes. Drinking efficiency and free wate r intake in home cages were unchanged. By comparing the effects of ris peridone in the present paper with the effects of different neurolepti cs in the same procedure from an earlier study, it appears that the ef fect of risperidone is intermediary to that of the 'typical' and 'atyp ical' neuroleptics. It may be concluded that risperidone acts as an at ypical neuroleptic compound; however, increasing the dose only two-fol d will cause EPS.