The heroin and prescription painkiller epidemic is bad enough, but now a deadly new opioid threat has arrived in the Garden State called “gray death.”

“Gray death is a combination of heroin, which is a natural opioid, fentanyl, carfentanil and U-4,” said Dr. Indra Cidambi, an addiction medicine expert, director and founder of the Center for Network Therapy in Middlesex.

She explained carfentanil is a synthetic opioid used to tranquilize elephants, and U-4, also known as pink on the street, is such a powerful synthetic opioid that literally one tiny grain of it can kill you.

“The combination of these drugs makes it deadly, overdose is inevitable, and this is really scary to us,” she said.

Cidambi pointed out gray death looks like concrete.

“It’s like small chunks of concrete. It can be injected, smoked, snorted and swallowed, and the potency is very high.”

She noted sometimes gray death can be absorbed through the skin just by touching it.

She explained 15 to 30 milligrams of heroin will get someone high, but fentanyl is so strong only 1 milligram will produce a high.

“However, a single grain of carfentanil, the size of a grain of salt, is so powerful it can lead to death,” she said.

“Fentanyl is a hundred times more powerful than heroin, and carfentanil is a hundred times more powerful than fentanyl. It’s amazing. So this is deadly, this whole combination is deadly.”

She explained when gray death is ingested, “there’s a sudden drowsiness, sudden sedation, slowed breathing. They get disoriented, they have pin-point pupil, and breathing stops."

She noted carfentanil does not even lead to addiction: It’s so much more powerful a narcotic that it just leads to death.

She said for years we’ve seen fentanyl mixed with heroin in New Jersey, and there are now reports of gray death beginning to show up in towns across the Garden state.

Cidambi said the synthetic opioid U-4, also referred to as U-47700, was created back in the 1970s to treat cancer, but it never got FDA approval.

She pointed out perhaps the scariest thing about gray death is addicts can’t wait to try it.

“Unfortunately, these addicted individuals constantly seek new highs, and want to experiment with more powerful drugs, and they’re willing to risk their life in search of a new high.”

She noted Narcan has literally saved the lives of thousands of overdose victims in New Jersey. “But, unfortunately, when they use gray death, the Narcan may not be able to reverse the overdose.”

She added a variety of dangerous chemicals can also be used in gray death concoctions.

“Most synthetic opioid drugs are being produced in China, so we really have to stop this at the source,” she said.

You can contact reporter David Matthau at

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