Olanzapine in the treatment of low body weight and obsessive thinking in women with anorexia nervosa: a randomized, double-blind, placebo-controlled trial

Am J Psychiatry. 2008 Oct;165(10):1281-8. doi: 10.1176/appi.ajp.2008.07121900. Epub 2008 Jun 16.


Objective: Anorexia nervosa is associated with high mortality, morbidity, and treatment costs. Olanzapine, an atypical antipsychotic, is known to result in weight gain in other patient populations. The objective of this trial was to assess the efficacy of olanzapine in promoting weight gain and in reducing obsessive symptoms among adult women with anorexia nervosa.

Method: The study was a double-blind, placebo-controlled, 10-week flexible dose trial in which patients with anorexia nervosa (N=34) were randomly assigned to either olanzapine plus day hospital treatment or placebo plus day hospital treatment.

Results: Compared with placebo, olanzapine resulted in a greater rate of increase in weight, earlier achievement of target body mass index, and a greater rate of decrease in obsessive symptoms. No differences in adverse effects were observed between the two treatment conditions.

Conclusions: These preliminary results suggest that olanzapine may be safely used in achieving more rapid weight gain and improvement in obsessive symptoms among women with anorexia nervosa. Replication, in the form of a large multicenter trial, is recommended.

Trial registration: ClinicalTrials.gov NCT00260962.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Anorexia Nervosa / diagnosis
  • Anorexia Nervosa / drug therapy*
  • Anorexia Nervosa / psychology
  • Antipsychotic Agents / adverse effects
  • Antipsychotic Agents / therapeutic use*
  • Benzodiazepines / adverse effects
  • Benzodiazepines / therapeutic use*
  • Body Mass Index
  • Body Weight / drug effects*
  • Combined Modality Therapy
  • Compulsive Behavior / diagnosis
  • Compulsive Behavior / drug therapy
  • Compulsive Behavior / psychology
  • Day Care, Medical
  • Double-Blind Method
  • Female
  • Humans
  • Length of Stay
  • Obsessive Behavior / diagnosis
  • Obsessive Behavior / drug therapy*
  • Obsessive Behavior / psychology
  • Olanzapine
  • Thinking / drug effects*
  • Thinness / drug therapy*
  • Thinness / psychology


  • Antipsychotic Agents
  • Benzodiazepines
  • Olanzapine

Associated data

  • ClinicalTrials.gov/NCT00260962