RESUMEN
Though the anticholinergics are associated with a variety of disadvantageous side effects, they are the most frequently prescribed pharmacological agents in the treatment of neuroleptic induced extrapyramidal manifestations in psychiatric population. A young adult male with chronic residual schizophrenia who developed acute psychosis following the administration of the modest doses of benztropine mesylate was described. In the light of this case two relevant issues including aggravated schizophrenia like psychosis and toxic psychosis were discussed. It was concluded that patients with residual schizophrenia developing aggravation in psychosis temporally induced by anticholinergics should be monitored carefully in particular for CNS toxic manifestations which would help in guiding the appropriate therapy for emerging toxic psychosis