Dude, after some quick reading on this, I would stay far away from this shit. It was an approved drug that got taken off the market. High potential for side effects and death. Fuck that shit.
Try low carb instead. Its worked wonders for me I've lost 50lbs over the past year and have not limited portion size at all. I love losing weight without being hungry. And I eat great food, I just have to limit the kinds of food I eat. Works very well for me, cause I love meat - cooked a pork shoulder last weekend, fatty as hell but I still lost a pound or to this week. Try it before going some way that will seriously jeopardize your health.