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.