Modafinil-associated weight loss in a clozapine-treated schizoaffective disorder patient

Ann Clin Psychiatry. 2005 Apr-Jun;17(2):95-7. doi: 10.1080/10401230590932407.


Background: We report a case of weight loss associated with modafinil-initiation in a clozapine-treated man with schizoaffective disorder.

Methods: To report the impact of modafinil, a wake promoting agent that lacks the unwanted side affects brought on by many psychostimulants, on weight in a clozapine-treated patient.

Results: Modafinil was initiated, and over the course of 1 year, Mr. B. experienced a weight loss of 40 lbs (from 280 lbs to 240 lbs) and a reduction in body mass index (BMI) of 5.08 Kg/m2 (from 35.52 Kg/m2 to 30.44 Kg/m2). After 3 years on the combination of clozapine and modafinil, his weight stabilized at 230 lbs (BMI = 29.59 Kg/m2). A 30-lb weight gain over a 6-month period occurred following discontinuation of modafinil. Reinstitution of modafinil resulted in a 10-lb. weight loss over a 6-week period.

Conclusions: Modafinil treatment resulted in a significant weight loss in this patient, possibly due to reducing clozapine-associated fatigue. Randomized placebo-controlled trials are necessary to evaluate the safety and efficacy of modafinilfor clozapine-associated weight gain.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Antipsychotic Agents
  • Benzhydryl Compounds / adverse effects*
  • Benzhydryl Compounds / therapeutic use*
  • Body Mass Index
  • Central Nervous System Stimulants / adverse effects*
  • Central Nervous System Stimulants / therapeutic use*
  • Clozapine
  • Drug Interactions
  • Fatigue
  • Humans
  • Male
  • Modafinil
  • Psychotic Disorders / drug therapy*
  • Weight Loss / drug effects*


  • Antipsychotic Agents
  • Benzhydryl Compounds
  • Central Nervous System Stimulants
  • Clozapine
  • Modafinil