Xylazine was approved by the F.D.A. for veterinary procedures in 1972. Since then, it has been used for procedures on sheep, deer, elk and even cats and dogs, as well as on horses and cattle. Earlier trials in humans had been shut down because the drug led to respiratory depression, so manufacturers never sought approval for human use. Until now, there has been insufficient incentive to research its impact on people. Its causal relationship to the flesh wounds that can result from its use is not understood. And unlike the protocols for opioids, those for reversing tranq dope withdrawal or managing rehabilitation have not been standardized.
Last month, a bipartisan bill introduced in both chambers of Congress by members from rural states — including Nevada, Iowa, New Hampshire, California, Florida, Texas and Colorado — offered a compromise. Rather than listing xylazine as a controlled substance, the bill proposes that a person who employs it for “illicit” purposes — sales or distribution for human use — would face the same penalties as if it were listed as a Schedule III drug, including fines up to $500,000 and a first-offense sentence of up to 10 years in prison.
Controlled substances are classified according to medical need and potential for abuse and addiction. Schedule III includes buprenorphine, the medication used to treat opioid use disorder. By comparison, Schedule I includes heroin and L.S.D. Schedule II includes oxycodone and fentanyl, which can be prescribed for pain.
Legislators said this path represented a hard-fought middle ground for bipartisan buy-in and, they hope, a fast track to passage.
“We need to make sure that we make it illegal for human use because of the devastating impact we see, but I also know, working with cattlemen and the ranchers in my state, that they need to be able to treat their horses and large animals with this drug,” said Sen. Catherine Cortez Masto, a Nevada Democrat, who introduced the bill with Sen. Chuck Grassley, an Iowa Republican, and Sen. Maggie Hassan, a New Hampshire Democrat.
Their bill has been endorsed by veterinary, rancher and police associations. If enacted, it would require manufacturers to enhance xylazine record-keeping and send tracking reports to a D.E.A. database. Law enforcement agents could pursue dealers.