The role of olanzapine in the treatment of anorexia nervosa

OBJECTIVE: To evaluate the role of olanzapine in the treatment of anorexia nervosa. DATA SOURCES: Literature was obtained through searches of MEDLINE (1966-December 2006), EMBASE (1980-4th Quarter 2006), and PsycINFO (1985-December 2006) and a bibliographic review of published articles. Key terms used in the searches included anorexia nervosa, antipsychotics, eating disorders, olanzapine, and Zyprexa. STUDY SELECTION AND DATA EXTRACTION: All English language articles that were identified from the search were evaluated. All primary literature was included in the review. DATA SYNTHESIS: In several case reports and most clinical trials, patients with anorexia nervosa successfully gained weight while being treated with olanzapine. Moreover, many patients treated with olanzapine achieved a healthy body weight. Case reports and trials identified additional benefits of olanzapine, including reduction in delusional thinking; improvement in body image, sleep, depressive symptoms, adherence to treatment, and eating-disorder symptoms; and decreased agitation and premeal anxiety. CONCLUSIONS: Preliminary evidence supports the use of olanzapine for treatment of anorexia nervosa by demonstrating that olanzapine 2.5-15 mg daily promotes weight gain and has positive effects on associated psychological symptoms. Limitations of the reported data include small sample size, low completion rate in clinical trials, and open-label trial design. Although olanzapine appears to have a potential role in the treatment of anorexia nervosa that has been unresponsive to other therapy, randomized, placebo-controlled studies with larger sample sizes are necessary to establish its role in therapy.