A study of quetiapine: Efficacy and tolerability in psychotic adolescents

Objective: To study the effectiveness, safety, and tolerability of quetiapine in adolescents with psychotic disorders. Methods: This study was an 8-week, open trial using quetiapine with 15 adolescents, ages 13-17 years, mean age 15.1 years, with a diagnosis of a psychotic disorder. Our primary instruments focused on psychotic symptomatology as measured by the Brief Psychiatric Rating Scale (BPRS), Clinical Global Impression (CGI), Positive and Negative Syndrome Scale (PANSS), and the Young Mania Rating Scale (YMRS). Other measures included adverse events, clinical laboratory tests, vital signs, electrocardiogram (ECG), extrapyramidal (EPS) measures, and ophthalmologic examination. Results: Quetiapine significantly reduced psychotic symptoms as measured by the BPRS, PANSS, YMRS, CGI, and CGI Severity of Illness scale. The average weight gain was 4.1 kg. After correction for expected weight gain, the mean weight gain over the 8-week period was 3.4 kg. Prolactin and cholesterol remained unchanged. Trends were found for a decrease in T₄ and an increase in thyroid-stimulating hormone. Common adverse effects were somnolence, agitation, drowsiness, and headache. No significant findings were noted on repeat ECGs, EPS measures, or ophthalmic examination. The final average treatment dose was 467 mg/day (range 300-800 mg/day). Conclusions: Quetiapine is suggested to be effective treatment of youths with psychotic disorders and to have a favorable side-effect profile.