Here are some common side effects of Invega Sustenna: weight increase, weight decrease, decreased appetite, increased appetite. I'm glad you're fine after going off the medicine. Being off the medicine means you no longer have the listed effects influencing you, but it doesn't mean you are gifted with a decreased appetite or weight loss. I'm afraid you simply return to whatever appetite is normal for you. You will probably have to work at losing any weight you gained. How long it takes depends on your metabolism plus eating habits and exercise. The biggest influence on your weight seems to come from what you eat. It's a rough deal, not fair at all, I'm afraid.