The use of exogenous sources of Growth Hormone has been popular in the United States for almost 8 years now. Originally, athletes used biologically active forms that were the actual extract of the pituitary glands of cadavers. Ascellacrin and Crescormon were the two most popular brand names on this original GH. While production was under way on the synthetic, recombinant DNA versions of this drug, it was discovered that the biologically active form was associated with the formation of a rare brain virus called Creutzveldt Jacob Disease. This was a fatal virus that afflicted a very small number of GH users, none of whom were athletes. In light of this discovery, the FDA removed all of these natural GH versions from the market in the United States. Luckily, the synthetic recombinant versions were approved by the FDA a short time afterwards.