Over-the-counter pills to lose weight include chinese herbal slimming pills, Ali and Phenphidrene. MetRx is one of the first diet pills to efficiently burn fat and suppress the appetite. MetRx is also known to boost metabolism, energy and mood. Many MetRx uses lose 3 to 6 pounds a week. Alli is supplement to be taken in conjunction with a low calorie diet and exercise. Alli users tend to lose 50% more weight than dieters who do not take Alli. Phenphidrene contains a number of stimulants that suppress appetite and give dieters energy. This pill does make some users feel shaky and edgy, but they report an average amount of weight loss as four to five pounds a week while using Phenphidrene.