The fight for a drug that's good for horses but horrible for humans

Drug dealers mix xylazine, an animal tranquilizer used by veterinarians, with fentanyl, with deadly results. But controlling it is tricky.

Penny, a 3-year-old chestnut mare with a white blaze, was drooling her food and fighting, signs of a probable toothache. An exam confirmed that she needed to extract two wolf teeth and grind down the sharp edges of some molars, procedures that required opening her jaws with a speculum.

To protect Penny from pain, and to protect herself from a horse kick that made her tenfold, Boyd Spratling, Penny's veterinarian, gave her an injection of xylazine, a common animal tranquilizer. Within moments, her long neck drooped and her eyelids fluttered. Forty-five minutes later, with dental surgery complete, Penny walked out of the clinic into rural Nevada and into her trailer.

For Dr. Spratling, xylazine is a vital painkiller and sedative, which he also occasionally uses in cattle, for procedures such as cesarean sections in cows and penile wound repairs in bulls. It is also a staple food for zoo veterinarians.

But in recent years the drug has also morphed into something else: a cheap and addictive illicit fentanyl adulterant that is contributing to rising deaths by overdose worldwide. country. The xylazine-fentanyl combo, known in the drug trade as "tranq dope", is a potentially deadly mixture that depresses breathing, heart rate and blood pressure, and can cause blackened flesh sores, similar to chemical burns, which can lead to amputation.

In a March xylazine alert, the Drug Enforcement Administration said that in 2022 it detected the drug in nearly a quarter of fentanyl samples confiscated in 48 states.< /p>

Last week, the White House's Office of National Drug Control Policy named drug mixing an "emerging threat related to drugs,” a classification that requires the office to design a government-wide response plan. But dealing with the threat is proving to be a delicate balancing act involving stakeholders in fields as disparate as addiction medicine, commercial breeding and law enforcement. At stake is to exercise caution in managing a drug that is essential for vets but fueling a public health crisis.

Law enforcement is pushing for that xylazine be listed as a controlled substance, which would criminalize distribution for human use. Currently, the police cannot arrest a person for selling or distributing xylazine. Their resources for tracking its production are modest. A controlled substance designation would make a crucial difference, law enforcement officials said.

But vets fear that if that happens, their access to the drug would be heavily regulated. They should keep separate logbooks for federal inspection. More worrying: producing a classified drug would require additional quality controls and safety measures so costly that a manufacturer could raise the price of the drug or simply stop making it.

"When we started seeing on the news that xylazine was mixed with fentanyl, we were horrified," said Dr. Spratling, who keeps his xylazine in a double-lock container.

But, he added, "let's not shoot the hip, because then the people who really pay the price, in terms of regulations, are the ones who have it used responsibly from the beginning."

Some addiction medicine specialists and harm reduction groups have different concerns. They fear tough new restrictions could trigger a domino effect of the kind that contributed to the fentanyl crisis, including criminal prosecutions of people with substance use disorders.