Um, I definitely wouldn't call HCG a drug, since it's a natual substance created by the human body, not a chemical invented by Big Pharma.
Taken with a specific low calorie diet, HCG eliminates hunger, allows the body to utilize fat stores that are not normally accessible, and at the same time preserves health and energy. For a thorough explanation, do a search for "A.T.W. Simeons" -- the European physician who developed the HCG protocol and helped many many many obese people -- and download his free 50-page book, Pounds and Inches. It's a book that has changed lives!!!