CHICAGO (WLS) -- A powerful tranquilizer is the new menace poisoning Chicago area street drugs and the people who use them.
It's called xylazine, also known by the street name "tranq." For people who use illict drugs it can be unseen and potentially fatal.
Drug traffickers are suspected of secretly adding xylazine to more expensive opioid products to cut costs and increase highs. But the drug, which is not intended for human use, can produce terrible side effects including gruesome wounds, amputations and death.
Click here to read the DEA's xylazine fact sheet
When Thomas Benson Krausmann died at the age of 29 in October 2021, there was a significant amount of xylazine listed on his toxicology report.
"He was a delightful guy, very inquisitive, very, very intelligent," said his father Tom Krausmann.
The Krausmanns said their compassionate and musically talented son started experimenting with illegal drugs like Oxycontin and Norco in high school. Then, they said, he moved on to heroin.
"Because the pills got harder to get and the heroin was very, very cheap," explained his mother Laura Krausmann.
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The Krausmanns originally thought he died from a heroin and fentanyl overdose, but months later a toxicology report from Lake County revealed something they couldn't have imagined and never even heard of.
"There wasn't any heroin in his body, it was xylazine and fentanyl," said Tom Krausmann.
He also said that back in 2021 the coroner was unfamiliar with the drug. The powerful animal tranquilizer is not intended for humans. Many people are unaware it might be in their street-bought drugs.
The Krausmanns said their son never would have intentionally ingested the potent and complicated drug mixture. They said this was not a drug overdose but a poisoning.
What they learned from drug experts was shocking: the amount of xylazine in his system alone would have killed him, and the amount of fentanyl "would have dropped an elephant."
DEA pamphlet on xylazine and its mixture with illicit drugs
Xylazine's toxic effects in humans aren't well understood. Users can be knocked out for hours, and there's a mysterious flesh-eating effect that leaves some users with horrific, hard to heal wounds that can lead to amputation.
Brooke Peder, an illicit substance user in Philadelphia, has been exposed to xylazine. As a result, her body is covered in hard-to-treat sores and she had to have her leg amputated. She may now lose an arm.
"The black dots, that's necrotic flesh. This actually looks phenomenal, right now," she said of her arm.
Philadelphia is currently ground zero for xylazine in the U.S. and is seeing some of the worst effects.
Now Cook County researchers are reporting a significant spike.
Dr. Neeraj Chhabra is an emergency room physician and medical toxicologist with Cook County Health. He studied death reports from Cook County that were fentanyl-related from 2017 to 2021. Chhabra said xylazine was rarely detected until a couple years ago.
"In 2021 and 2022 those numbers kept rising so we were surprised by it. We've seen it in other parts of the country so we knew that was probably a real, real trend that was happening here," he said.
FDA alert on xylazine exposure
"The increase in the incidence of xylazine is concerning because it is not an opioid," said Cook County Chief Medical Examiner Dr. Ponni Arunkumar. "So it does not get affected by naloxone that is used to reverse fentanyl. It is not as potent as fentanyl but it kind of makes the effects of fentanyl worse."
Live4Lali works with and provides support for people and families impacted by substance use. Their outreach effort now includes flyers warning about xylazine and wound care kits.
"This has really rocked our world," said executive director Laura Fry. "When we encounter someone that has wounds of course we want them to go to the hospital. These aren't going to heal on their own."
The organization serves the Chicago suburbs. Fry said they have just started seeing some of the xylazine wounds out in the community.
An I-Team data analysis found xylazine-related deaths in Cook County tripled from 2020 to 2021, going from 42 to 125. In 2022, those numbers climbed again by nearly 20%.
Many medical examiners in suburban counties said they're also seeing cases.
The local drug supply is now under the microscope, being monitored by Chicago Recovery Alliance. Experts there said they are the first the area now evaluating chemical strips that could detect the presence of xylazine.
Taylor Wood is heading the effort to help get the test strips approved for spot checking illicit drugs being sold on the street as lead technician and drug checking program manager for Chicago Recovery Alliance.
"I'm absolutely worried about xylazine, especially since it has taken us a long time to recognize its presence in the supply," he said. "I don't want people to be scared, I just want them to be proactive."
The Krausmann family is urging that there be more resources, awareness and kindness.
"He knew that I valued him. It didn't solve his problems, but it gave him great comfort," said Tom Krausmann.
"He wasn't alone in the world. The stigma has got to go away. We have to stop treating them like they are bad. They're not," said Laura Krausmann.
Xylazine is not listed as a government controlled substance so it ends up in a legal grey area. The DEA is reporting it is very likely the prevalence of the animal tranquilizer is widely underestimated across the country.
Researchers are calling for expanded testing so communities have a better idea of how big a problem the animal tranquilizer is becoming across the country.