According to research by Dr. CB Nemeroff, a dosage of 5/mg of Zyprexa causes an average weight gain of approximately 15lbs. Dosages above 20/mg per day have most frequently been associated with extra weight. Olanzapine is associated with weight gain which according to recent studies may put olanzapine-treated patients' offspring at a heightened risk for neural tube defects (e.g. spina bifida). Although it is one of the most commonly prescribed and effective AATPs, olanzapine causes the most weight gain and metabolic impairments in humans. To characterize its metabolic effects, we adopted an olanzapine-supplemented diet to reproduce human plasma olanzapine levels in female C57BL/6 mice ( 18 ). Yes, olanzapine is well known to cause weight gain by slowng down glucose and lipid metabolism, its a very effective drug though. Introductio­­n. This article, written primarily for people with mental health problems and their carers, is about weight gain with antipsychotic medication. Because olanzapine stimulates the appetite area of the brain, it causes many people to gain weight. Rapid olanzapine weight gain Darrell had a rapid “olanzapine weight gain”, gaining 35 pounds in two months. Zyprexa (Olanzapine) is an atypical antipsychotic medication that is approved by the FDA for the treatment of schizophrenia and bipolar disorder. Since weight gain contributes to non-compliance with treatment and may lead to medical morbidity, it is important to know and study the causes of weight gain associated with the use of the atypical antipsychotic olanzapine. Weight gain, which can lead to diabetes, is a major side effect. As I said, it should be prescribed for schizophrenia and other instances of psychosis -- not for depression, not for insomnia, not for anything else. A 12-week, prospective study comparing adolescents with schizophrenia treated with olanzapine, risperidone and haloperidol showed 7.2 kg weight gain on olanzapine, with 90.5% gaining at least 7% of their baseline bodyweight, and 3.9 kg weight gain on risperidone, 42.9% gaining 7% or more of their baseline bodyweight, compared to 1.1 kg weight gain on haloperidol, with only 12.5% gaining 7% or.