Antipsychotic drugs, such as olanzapine (Zyprexa), risperidone (Risperdal) and quetiapine (Seroquel), are commonly used to treat psychotic disorders like schizophrenia, bipolar disorder and other behavioral problems. As effective as these drugs may be, the weight gain commonly experienced with them causes many patients to discontinue their use leading to even further problems.

A new study has evaluated an add-on treatment to potentially reduce weight gain side effects while on anti- psychotic treatment. In a randomized, double-blind, placebo-controlled trial, scientists 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 study participants received olanzapine, and half also received modafinil treatment while the other half received placebo. Three weeks after, the body mass index has increased in both groups, however those receiving olanzapine/placebo combination showed significantly greater weight increase than those receiving olanzapine/modafinil.

The researchers say that since modafinil showed promise in this short-term study on healthy individuals, it can now be evaluated as a "viable candidate for a larger, more complex clinical trial to determine efficacy in a patient population."

This finding may even encourage more research to see whether there are other benefits associated with modafinil prescription with regards to symptoms or cognitive impairments associated with schizophrenia.