Antipsychotic drugs are used to treat a wide variety of child psychiatric disorders characterized by psychotic symptoms, aggression, excitement, tics, stereotypies and hyperactivity nonresponsive to other therapies. Unfortunately, typical antipsychotics have many adverse effects limiting their long-term use. Novel antipsychotics with combined dopaminergic and serotonergic action, such as risperidone, appear to offer better safety and efficacy profiles in controlled studies of adult patients, and therefore appeared as promising pharmacotherapeutic agents in child psychiatry. The purpose of this retrospective chart review was to obtain data on the potential effectiveness and tolerability of risperidone in children and adolescents presenting with a variety of chronic and severe psychiatric disorders who had been unresponsive to previous pharmacological treatments. Charts for 106 children and adolescents (males n = 81 or 76.4%; females n = 25 or 23.6%), presenting with attention deficit and/or hyperactivity disorder (n = 49 or 46.2%), conduct disorder (n = 13 or 12.3%), oppositional-defiant disorder (n = 5 or 4.7%), behavioural problems not otherwise specified (n = 2 or 1.9%), autism (n = 8 or 7.5%), Asperger's syndrome (n = 8 or 7.5%), pervasive developmental disorder (PDD) not otherwise specified (n = 4 or 3.8%), anxiety (n = 6 or 5.7%), depression (n = 2 or 1.9%), dysthymia (n = 2 or 1.9%), schizophrenia (n = 4 or 3.8%), adjustment disorder (n = 1 or 0.9%) and obsessive-compulsive disorder (n = 2 or 1.9%) were reviewed retrospectively to determine the tolerability and potential efficacy of risperidone treatment for a variety of psychiatric disorders. Six subjects also presented with mental retardation. The average length of illness prior to risperidone treatment was 5 years and the average age of risperidone treatment onset was 11 years. The mean daily dose of risperidone was 1.2 mg (range = 0.25 to 8.0 mg). Very few adverse effects were reported. The average length of risperidone treatment was 11 months with the majority (n = 75 or 76%) of patients maintained on risperidone following study termination. Seven cases (6.6%) were missing follow-up data. The majority (n = 78 or 74%) of patients were taking concurrent psychiatric medications, most commonly stimulants for the treatment of ADHD. Clinical global improvements for children and adolescents at the final study visit were marked (n = .37 or 34.9%), moderate (n = .40 or 37.7%), mild (n = 13 or 12.4%), none (n = 12 or 11.3%), or worse (n = 1 or 1%). Three cases (2.9%) were missing clinical improvement data. Results suggest that risperidone may be useful for managing behavioural disturbances and psychotic symptoms associated with a wide variety of childhood psychiatric disorders. For most patients in the study, a combination of risperidone and adjunctive pharmacotherapy was beneficial. Controlled and discontinuation studies of risperidone treatment in children and adolescents with behavioural and psychotic disorders are recommended. (C) 2001 Elsevier Science Inc. All rights reserved.