Scientists uncover surprising new details about fentanyl/xylazine drug mixture

A breakthrough discovery could help with understanding why withdrawal from the mixture of fentanyl and xylazine is so severe. As Emily’s Hope has previously reported,  xylazine is a veterinary tranquilizer that is not intended for human consumption, but drug manufacturers are mixing it with fentanyl to create a dangerous new drug.

In a recent discovery, scientists at the University of North Carolina at Chapel Hill found that xylazine is a kappa opioid receptor agonist, meaning it activates kappa opioid receptors in the same way fentanyl activates opioid receptors. 

“Many people thought xylazine operated exclusively through a different mechanism in the nervous system,” Zoe McElligott, whose lab led the research, said in a press release. “But because we show xylazine is an agonist at kappa opioid receptors in the brain and body, in addition to acting at other targets, we may have gleaned insight into why withdrawal from the combination of fentanyl and xylazine is so harsh.”

McElligott said the discovery could also impact how doctors treat people suffering from a xylazine overdose, including the use of naloxone.

“A big ‘take-home’ message is that we want to make sure people are administered naloxone as a life-saving treatment,” McElligott said. “When xylazine first came on the scene, there was a lot of talk about how it wouldn’t respond to naloxone. Our data suggest otherwise, and we don’t want people to not administer naloxone because they suspect someone has xylazine in their system.”

This week, CBS News also reported that Pittsburgh is seeing a skyrocketing number of people with serious side effects from the “zombie drug.” The Allegheny County Medical Examiner’s Office told CBS News that almost 100 people have overdosed with xylazine in their systems since January 2023.

The drug mixture is often called the “zombie drug” due to its horrific side effects, which include skin rotting, open sores, and a disoriented gait. The excessive drowsiness caused by the drug can give users a zombie-like appearance, and it can even cause the skin to rot down to the bone.

“Necrosis of the skin down to the bone, they come in with just big festering wounds,” Allegheny Health Network Dr. Brent Rau told CBS News. “They’re going to need a great deal of wound care, debridement in the OR where they cut away the tissue, and in severe cases, amputation of the limb itself.”