A doctor from Provena St. Joseph's Medical Center in Joliet, Ill, has said that at least three people have shown signs of Krokodil -use in Chicago.

Other health experts, however, are sceptical about the claim.

Krokodil is the cheaper, home-made version of desomorphine. It is made using codeine and other easily available ingredients including gasoline, iodine and paint thinner. The drug is several times more potent than morphine and users develop green, scaly lesions, giving rise to the moniker "krokodil" or crocodile.

The drug first appeared in the remote regions of Russia in 2002. Recently, health authorities from Arizona had said that they had found cases of potential desomorphine-use in the state.

Dr. Abhin Singla, director of addiction services at Presence St. Joseph Hospital, told Chicago Tribune that three women with rotting flesh arrived at the hospital's emergency room. He said that the patients reported using krokodil. Last week two more men came into the ER with similar symptoms, he added.

"It is a horrific way to get sick," said Dr. Singla, The Chicago Tribune reported. "The smell of rotten flesh permeates the room."

Dr. Syed Bokhari, a surgeon who treated one of the women said that he had never seen such horrible skin wounds, despite operating on several people during his 20-year career.

But, are these people really using desomorphine?

Frank LoVecchio, co-medical director of Phoenix-based Banner Poison Control and Drug Information Center told The Los Angeles Times that none of the reported cases in the U.S. have been confirmed as health authorities don't have access to original injected substance.

Dan Bigg, director of the Chicago Recovery Alliance, said that the "rotting, greenish flesh" could be due to victims using contaminated heroine or dirty needles.

"In 24 years of almost daily contact with opiate users, I have never seen it, nor have I heard of anyone who has used it (desomorphine)," Bigg told the Chicago Tribune. "There would be no reason to use it here. Codeine is not readily available. Heroin is easily available, and costs $5 or $10 (per dose). Why would someone want to mix gasoline with their drugs if they didn't have to?"

The Drug Enforcement Administration recently told Fox News that it hasn't found the drug in the country.