Doctors at St Mary's Heath Center have come forward with the story of a patient they treated in December 2012.
The 30-year-old man's finger had rotted, turned black and fallen off.
He also had severe ulcers across both thighs.
The drug addict told doctors that eight months earlier he started using a substance called Krokodil - the Russian name for crocodile - that got its name from turning users skin green and scaly
According to STL Today (external - login to view) the man said he had turned to the drug because he could no longer afford his $300-a-day heroin habit.
Desomorphine, the drug’s official name, is made by cooking prescription painkillers with contaminants such as gasoline, alcohol, paint thinner or lighter fluid.
The drug produces a high similar to heroin but is much cheaper to make and more addictive.
Read more: First US Krokodil drug case recorded by doctors in St. Louis | Mail Online
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This is scary, what next will they concoct just to get a high.