In a randomised, double-blind, placebo-controlled trial, Dr. James Roerig and colleagues evaluated the effect of modafinil on olanzapine-associated weight gain in normal volunteer subjects. Modafinil is a drug currently used to increase wakefulness in individuals with sleep disorders, such as narcolepsy. All of the subjects received olanzapine, and half also received modafinil treatment while the other half instead received placebo. After three weeks, although the body mass index was increased in both groups, those receiving olanzapine/placebo showed significantly greater weight increase than those receiving olanzapine/modafinil.
Dr. Roerig notes that now that this short-term study in healthy individuals has shown promise, modafinil can now be evaluated as a "viable candidate for a larger, more complex clinical trial to determine efficacy in a patient population."
Dr. John Krystal, Editor of Biological Psychiatry and affiliated with both Yale University School of Medicine and the VA Connecticut Healthcare System, agrees that further research is warranted. "Psychiatrists are now working more closely with patients to manage the side effects of antipsychotic treatment. The finding that modafinil reduces weight gain may encourage more research to see whether there are other benefits associated with modafinil prescription with regards to symptoms or cognitive impairments associated with schizophrenia."