Risperidone-induced sialorrhea responsive to biperiden treatment.

Materials and methods The patient was an 18 year old female suffering from schizophrenia, paranoid type. She had no history of any medical condition. The onset of her psychiatric condition was at the age of 17. Due to low adherence, she had never taken any medications and had no previous hospitalizations. During her hospitalization, she was started on 1mg/ d lorazepam and 2mg/d risperidone (with a gradual increase up to 6mg/d on day 3, due to lack of response and progressive thought disorganization). On day 4 the patient exhibited hypersalivation and a concomitant mild speech disturbance. No signs of EPS where present except for mildly impaired postural reflexes that could be considered as a sign of imminent EPS. Subsequently, risperidone was tapered to 3mg/d along with oral biperiden 2mg/d resulting to full remission of hypersalivation by day 5.