Olanzapine versus placebo for out-patients with anorexia nervosa

Psychol Med. 2011 Oct;41(10):2177-82. doi: 10.1017/S0033291711000390. Epub 2011 Mar 22.


Background: Anorexia nervosa (AN) is a serious psychiatric illness associated with significant morbidity and mortality. There is little empirical support for specific treatments and new approaches are sorely needed. This two-site study aimed to determine whether olanzapine is superior to placebo in increasing body mass index (BMI) and improving psychological symptoms in out-patients with AN.

Method: A total of 23 individuals with AN were randomly assigned in double-blind fashion to receive olanzapine or placebo for 8 weeks together with medication management sessions that emphasized compliance. Weight, other physical assessments and measures of psychopathology were collected.

Results: End-of-treatment BMI, with initial BMI as a covariate, was significantly greater in the group receiving olanzapine [F(1, 20)=6.64, p=0.018]. Psychological symptoms improved in both groups, but there were no statistically significant group differences. Of the 23 participants, 17 (74%) completed the 8-week trial. Participants tolerated the medication well with sedation being the only frequent side effect and no adverse metabolic effects were noted.

Conclusions: This small study suggests that olanzapine is generally well tolerated by, and may provide more benefit than placebo for out-patients with AN. Further study is indicated to determine whether olanzapine may affect psychological symptoms in addition to BMI.

Trial registration: ClinicalTrials.gov NCT00692185.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Analysis of Variance
  • Anorexia Nervosa / drug therapy*
  • Antipsychotic Agents / therapeutic use*
  • Benzodiazepines / therapeutic use*
  • Body Mass Index
  • Double-Blind Method
  • Female
  • Humans
  • Male
  • Middle Aged
  • New York
  • Olanzapine
  • Ontario
  • Outpatients
  • Placebos
  • Psychiatric Status Rating Scales
  • Treatment Outcome
  • Weight Gain / drug effects*
  • Young Adult


  • Antipsychotic Agents
  • Placebos
  • Benzodiazepines
  • Olanzapine

Associated data

  • ClinicalTrials.gov/NCT00692185