Effectiveness, Adverse Effects and Drug Compliance of Long-Acting Injectable Risperidone in Children and Adolescents.

Background And Objectives: Although the use of oral risperidone in children and adolescents has been well studied, there is little information on the intramuscular use of long-acting injectable risperidone (LAIR). The aims of this study were to investigate the effectiveness and adverse effects of LAIR in children and adolescents with conduct disorder, bipolar disorder, and schizophrenia.

Methods: In total, 42 patients (age range 12-17 years) who were non-adherent to oral antipsychotic drugs, received 25 mg of LAIR intramuscularly every 2 weeks. The drug was administered at least four times and up to 66 times (median drug use: 9.50 times). The effectiveness and adverse effects of the treatment were examined.

Results: There was an improvement in 13 (92.8%) of the 14 patients diagnosed with bipolar disorder, in 25 (78.1%) of 32 patients diagnosed with conduct disorder and in one (50%) of two patients diagnosed with schizophrenia. Six patients had comorbid conduct disorder and bipolar disorder. Totally, 81% of the patients improved with LAIR. Weight-gain, daytime somnolence, muscle stiffness and spasms, impaired concentration, and fatigue were the most common side effects through the whole sample. Menstrual problems were common in girls. In the study, 57.1% of the patients continued to receive their injections regularly until the end of the treatment, under physician control. A total of 16.7% discontinued the treatment due to non-adherence. The LAIR treatment was terminated in 26.2% of the patients, due to weight-gain, dystonia, and galactorrhea.

Conclusions: In children and adolescents with conduct disorder, bipolar disorder and schizophrenia who show noncompliance with oral drugs, LAIR may improve treatment compliance. LAIR is a reliable treatment in terms of its effectiveness. Weight-gain, dystonia, and galactorrhea were the adverse effects that were responsible for LAIR treatment cessation.