Last week Science Daily had a brief article noting the association of contaminated cocaine with ear necrosis: Contaminated Cocaine Triggers Decaying, Dying Skin (photo credit)
According to Mary Gail Mercurio, M.D., an author and associate professor in the Department of Dermatology at the University of Rochester Medical Center, "When we first started seeing these patients they all had a similar clinical picture, but they were really an enigma because they weren't falling into any other pattern we'd seen before. When a colleague at the National Institutes of Health mentioned levamisole contamination, we did toxicity screens and lo-and-behold, all the patients came up positive for cocaine. We had our diagnosis."Drug enforcement officials have detected levamisole -- which was once used to treat colon cancer -- in cocaine since 2003, but have watched it increase rapidly in recent years. The Drug Enforcement Administration says that the drug, which is inexpensive, is used more and more as a diluting agent in order to stretch supplies. Study authors report that levamisole is known to increase dopamine, a neurotransmitter that helps control the brain's reward and pleasure centers, causing experts to believe it is also added to cocaine to further enhance or prolong the user's high.Researchers don't know how levamisole causes purpura, which occurs when vessels become plugged and blood can't flow to the skin, leading to skin death and the resulting purplish, crusty appearance. Cocaine alone constricts blood vessels, which is probably the first step, but how levamisole contributes is not yet understood, Mercurio said.