Early onset of schizophrenia (before the age of 18 years) is associated with a higher risk of delayed or missed diagnosis, more severe course of the disease, and an increased susceptibility to adverse reactions to antipsychotic drugs. The objective of this paper is to present the recommendations for the diagnostic and therapeutic management of patients with early-onset schizophrenia, developed on the basis of a literature review and a consensus of a group of experts working with schizophrenia therapy. The formal criteria that must be met to diagnose schizophrenia are the same for children and adults. Early-onset schizophrenia must be thoroughly differentiated from uni - or bipolar affective disorder, autism-spectrum disorders (ASDs) and anxiety disorder. Diagnostic assessment for psychotic disorders is also necessary in the case of abnormal, destructive or aggressive behaviour, or self-harm. The mainstay of schizophrenia treatment is pharmacological therapy, which is used in the treatment of acute episodes and in maintenance treatment - prevention of relapses. However, the use of pharmacological interventions in children and adolescents only to reduce the risk of psychosis development is not justified. Antipsychotic agents significantly differ by their tolerance profile and clinical efficacy. Second-generation antipsychotic agents approved for the treatment of early-onset schizophrenia - aripiprazole, lurasidone and paliperidone - enable its effective and safe treatment. The necessary complement to pharmacological therapy is non-pharmacological interventions that should be adapted to the patient\'s age, cognitive abilities, disease stage and the needs of the whole family.

Schizophrenia spectrum and other psychotic disorders often have their onset in adolescence. The sequelae of these illnesses can negatively alter the trajectory of emotional, cognitive, and social development in children and youth if left untreated. Early and appropriate interventions can improve outcomes. This article aims to identify best practices in the pharmacotherapy management of children and youth with schizophrenia spectrum disorders.
A systematic search was conducted for published guidelines for schizophrenia and schizophrenia spectrum disorders in children and youth (under age 18 years). Recommendations were drawn from the National Institute for Health and Care Excellence guidelines on psychosis and schizophrenia in children and youth (2013 and 2015 updates). Current guidelines were adopted using the ADAPTE process, which includes consensus ratings by a panel of experts.
Recommendations identified covered a range of issues in the pharmacotherapy management of children and youth with schizophrenia spectrum disorders. Further work in this area is warranted as we continue to further understand their presentation in the developing brain.
Canadian guidelines for the pharmacotherapy management of children and youth with schizophrenia spectrum disorders are essential to assist clinicians in treating this vulnerable population. Ongoing work in this area is recommended.