Could 2.5 mg of zypreza cause a lot of weight gain?

What's a lot? Antipsychotics, especially the atypicals of which zyprexa (olanzapine) is an example, are associated w/metabolic side effects, including weight gain, high sugar (diabetes even), and high cholesterol, in addition to more common motor side effects. Talk to your doc about options as some are associated w/less weight gain than others. Of course, you 1st need a drug that takes care of your symptoms.