RALEIGH, N.C. – A dangerous drug trend involving an animal tranquilizer has made its way to counties across North Carolina.

UNC-Chapel Hill drug researcher Colin Miller says more than 130 samples of xylazine mixed with opioids, fentanyl, cocaine and heroin have been found.

“Xylazine is veterinary tranquilizer. It's an alpha-2 agonist. So, it's a very close relative to the drug clonidine,” Miller said. “If you're familiar with clonidine, which is used for blood pressure and things of that nature.”

The big difference is xylazine is a potent tranquilizer that’s used on horses and in a veterinary capacity. Xylazine has never been approved for human consumption.

Tell-tale signs of the drug are unique skin wounds.

“We are seeing a lot of really bad wounds that xylazine can cause. These wounds look more like a burn, if anything, and can take, you know, months and months to heal under the under optimal conditions,” he said.

Miller says people have been cutting drugs with xylazine for years, in areas of Puerto Rico, Philadelphia and Virginia, and now it’s spreading along the East Coast and to the Midwest.

“We’ve had positive tests for xylazine from counties sort of all over, from all the way up in the mountains to the coast and everywhere in between,” Miller said.

According to the UNC Drug Analysis Lab report, traces of the drug have been found in samples from 28 counties, with at least 133 cases so far.

“Xylazine is becoming sort of ubiquitous in the opioid supply, the black market opioid supply in North Carolina. We're seeing it in about ... 5% of the samples that we're analyzing that are expected to be or that are thought to be fentanyl or heroin,” Miller said.

Stay up to date on the cases and findings of the drug in North Carolina here.

You can follow developments in how xylazine is entering the drug supply on UNC scientist Dr. Nabarun Dasgupta's Twitter feed here.