Are There Any Anti-psychotic Drugs That Do Not Cause Weight Gain?

I have been hearing voices that tell me what to do-where things are-what I see- I hear conversations that I have with people-they usually start in mornings and happen at night when I m tired. my wellburtin was increased from 150mgs. to 300 mgs. I quit taking trazodone ,zolpidom and was introduced to buspar so I could be on a anxiety med that was not addictive like clonazepam. I was prescribed an anti psychotic med such as risperdone small dose of 5mgs. are there any medicines in this class that do not have weight as a side effect???