I was told that it's metabolic. I never overate, exercised, took metabolism boosters, and couldn't lose a pound. Since I went off the Invega close to 2 months ago, I've dropped 10 pounds without trying. Since I never had weight issues before meds, I can only conclude that the medications caused the rapid weight gain. I wish there was a better solution, but the only thing that worked for me was stopping the medication.