Olanzapine in the Treatment of Behavioral Problems Associated with Autism: An Open-Label Trial in Kuwait

Objectives: To study the efficacy and safety of olanzapine for the treatment of children with autism associated with disruptive behavior problems. Subjects and Methods: A prospective open-label trial was conducted on 40 male children (mean age 12.2 ± 2.2 years, range 7–17 years) meeting Diagnostic Statistical Manual IV criteria for autism. After a washout period from previous medications (2–14 days), patients received olanzapine (5–10 mg/day) for a 13-week treatment period. The primary efficacy measures were Aberrant Behavior Checklist (ABC) and Clinical Global Impressions-Severity (CGI-S) done at baseline and end of treatment. At the beginning and end of treatment, patients underwent laboratory and physical investigations: ECG, chest X-ray, urinalysis, serum chemistry, blood glucose and lipid profile, hematology and hepatitis B serology. Results: Paired comparison of baseline and 13-week endpoint scores showed significant reductions in ABC subscale scores for irritability (p 0.0001), lethargy (p 0.0001), stereotyped behavior (p 0.005), hyperactivity (p 0.0001) and inappropriate speech (p 0.005). Of 40 patients, 12 (30%) were considered as ‘improved’ on CGI-S scores compared to baseline, a statistically significant difference (p 0.05). No liver enzyme elevation or any other serum biochemical changes resulted from treatment, which was not associated with significant body weight changes or any other treatment-emergent side effects. Conclusions: The study shows that olanzapine treatment can be beneficial in alleviating some behavioral symptoms (irritability, hyperactivity/noncompliance and lethargy/withdrawal) associated with autism. The short period of this trial limits inferences about adverse effects such as body weight increase and tardive dyskinesia. Further long-term placebo-controlled studies of olanzapine are required.