Risperidone is used for the treatment of schizophrenia, bipolar disorder, and behavior problems in people with autism.^[4] In autism, however, it does not improve conversational ability or social skills, and does not appear to reduce obsessive behavior in most autistic people.^[4]

Due to its strong serotonin, dopaminergic, and adrenergic antagonism, risperidone was approved by the United States Food and Drug Administration (FDA) in 1993 for the treatment of schizophrenia.^[5] On August 22, 2007, risperidone was approved as the only drug agent available for treatment of schizophrenia in youths, ages 13–17; it was also approved that same day for treatment of bipolar disorder in youths and children ,ages 10–17, joining lithium. Risperidone contains the functional groups of benzisoxazole and piperidine as part of its molecular structure. In 2003, the FDA approved risperidone for the short-term treatment of the mixed and manic states associated with bipolar disorder. In 2006, the FDA approved risperidone for the treatment of irritability in children and adolescents with autism.^[6] The FDA's decision was based in part on a study of autistic people with severe and enduring problems of violent meltdowns, aggression, and self-injury; risperidone is not recommended for autistic people with mild aggression and explosive behavior without an enduring pattern.^[7] Like other atypical antipsychotics, risperidone has also been used off-label for the treatment of anxiety disorders, such as obsessive-compulsive disorder, severe, treatment-resistant depression with or without psychotic features, Tourette syndrome, disruptive behavior disorders in children, and eating disorders, among others. In two small studies, risperidone was reported to successfully treat the symptoms of phencyclidine psychosis due to acute intoxication^[8] and chronic use.^[9]