Personally I wouldn't recommend using chemicals, or doing crazy diets for weight loss. Sensible, healthy eating and a good exercise plan are the way to achieve sustainable weight loss and fitness. Don't waste your money on fad products, they are not good.
HCG is a prescription. The products available over the counter do not contain enough HCG to have any effect whatsoever. They are a SCAM. The real HCG diet worked great for me, but it has to be prescribed AND supervised by a doctor. Otherwise, you're going to really screw up your metabolism and send your body into starvation mode. The weight you lose will not be the abnormal fat you want to lose and will be regained. See a doctor or don't do it.