Are there any anti-psychotics that don't cause weight gain?

Just to rule out another anti-psychotic, Risperidal caused me to gain 40 lbs in just one summer and I was eating healthy and exercising. If your doctor is recommending anti-psychotics, it is much safer to try them and risk gaining weight as opposed to trying to manage without them. On that same note, though, keep in mind that anti-psychotics are SO HARD to come off of and can have scary side-effects.