Why you want to use pills when you can lose weight without using pills or supplements.
check this thread I just posted there
Orlistat (active ingredient in Xenical) is also the active ingredient used in the weight loss aid - Alli, which is the first OTC weight loss aid, approved by FDA as safe and effective for weight loss.
It does work and so far, seems to be safe. It works by blocking fat absorption. There are some unpleasant side effects if you don't eat properly, which is mainly avoiding fat. The main side effect is uncontrollable, oily, runny stools, if too much fat is consumed.
My endocrinologist prescribed Xenical for me, but the script was too expensive. Instead, I tried Alli, which did work and I lost about 8 pounds. I didn't have unwanted side effect because I was very careful about the amount of fat I consumed, but I didn't stick with it.