Are you saying that Lithium makes you require more calories than you can burn? How is that? Even if meds slow down your metabolic rate, you could still eat healthy, be full, not starve, and lose fat. I gained 40lbs on Lyrica due to increased appetite but increased appetite does not mean you would feel like you're starving when creating 200-300 calorie deficit. There are plenty of low calorie yet stomach filling foods out there to help with increased appetite.