By now, most veterinary professionals have probably heard about proposed changes in the scheduling of xylazine in the United States, but there is a lot of confusion about the details and what this means: Will it still be available in the future? Is it already illegal in some states? Is it being diverted from veterinary channels? 

NEWStat spoke with Lauren Forsythe, PharmD, DICVP, FSVHP, medication dispensary coordinator and clinical assistant professor at the University of Illinois College of Veterinary Medicine to get some clarification on veterinary use of xylazine at the state and federal levels.

Xylazine: An “immediate public health crisis”

According to Forsythe, xylazine was determined to be unsafe for humans in the 1960s and has never been approved for human use due to the risks of severe CNS depression and eschars requiring amputation in some humans.

Its popularity as an illicit street drug stems from its ability to increase and prolong the high users get from fentanyl and other drugs. But because of its dangerous consequences and the fact that there is no FDA-approved reversal agent for xylazine in humans, people who use a xylazine/opioid combination are at a higher risk of dying than they would be without the xylazine.

Forsythe explains that the severity of the xylazine epidemic has created an “immediate public health crisis” that requires action to block inappropriate access.

The DEA reported in 2022 that nonveterinary internet sites were selling xylazine in both liquid and powder formulations without any requirements to prove a legitimate, legal use.

Evidence of diversion from veterinary channels has also been discovered, Forsythe said: Bottles of pharmaceutical-grade xylazine from a veterinary distributor have been reported at sites in Philadelphia where dealers were preparing their drugs.

“Diversion has likely been going undetected due to the uncontrolled nature of xylazine and limited inventory systems in veterinary medicine,” she said.

Some diversion may involve theft: In 2020, a break-in at a Canadian veterinary hospital resulted in the theft of xylazine along with ketamine and detomidine.

What is being done about xylazine?

The US federal government and many state governments are taking steps to curb the availability of xylazine for street use. In February, the US Food and Drug Administration (FDA) announced that it would be reviewing all shipments of finished xylazine and the bulk chemical form used to produce it into the United States to try to stop nonveterinary forms of the drug from entering the country.

In addition, the federal government has begun the process of permanent scheduling of xylazine as a controlled substance. This is a long, multi-agency process that began in October 2021. Now that the DEA has completed their 8-Factor Analysis, future steps will involve Congress passing legislation to schedule xylazine, likely as a schedule III controlled substance. Separately, some states are passing (or have already passed) their own controlled substance legislation surrounding xylazine.

What about veterinary use of xylazine?

As of this writing, xylazine is still not controlled at the federal level. In the states where it is controlled, the effects on veterinary use vary. Florida, for example, scheduled xylazine as a schedule I controlled substance (for human use) in 2018 but did not include any mention of veterinary use in its legislation.

Ohio has classified it as a schedule III drug for both human and veterinary use. Other states have recently scheduled xylazine or are in the process of scheduling it anywhere from a schedule I to a schedule VI (in Massachusetts) controlled substance.

The AVMA is supporting legislation that would classify xylazine as a schedule III substance for human use but not a controlled substance at all for veterinary use. This would hopefully make it harder to smuggle illegitimate sources of the drug into the country and would allow for stricter penalties for those caught with it, but it would not do anything to curb veterinary diversion.

It will be important to follow developments at both the state and federal levels. Forsythe believes xylazine will likely eventually be a schedule III controlled substance for veterinary use, but most likely it will continue to be an option for veterinarians who wish to use it.

“If [veterinarians] are willing to use a controlled substance,” Forsythe said, “then they can continue using xylazine with the required safeguards and recordkeeping.”

Further reading

The Growing Threat of Xylazine and its Mixture with Illicit Drugs
https://www.dea.gov/sites/default/files/2022-12/The%20Growing%20Threat%20of%20Xylazine%20and%20its%20Mixture%20with%20Illicit%20Drugs.pdf

Will Xylazine Become a Controlled Substance?
https://www.medpagetoday.com/special-reports/exclusives/103244

Biden-Harris Administration Designates Fentanyl Combined with Xylazine as an Emerging Threat to the United States
https://www.whitehouse.gov/ondcp/briefing-room/2023/04/12/biden-harris-administration-designates-fentanyl-combined-with-xylazine-as-an-emerging-threat-to-the-united-states/

Congressional offices consider making xylazine a controlled substance
https://www.avma.org/blog/congressional-offices-consider-making-xylazine-controlled-substance

DEA Reports Widespread Threat of Fentanyl Mixed with Xylazine
https://www.dea.gov/alert/dea-reports-widespread-threat-fentanyl-mixed-xylazine

Emily Singler, VMD, is a 2001 graduate of Penn State University and a 2005 graduate of University of Pennsylvania School of Veterinary Medicine. She has worked in shelter medicine, private practice, and as a relief veterinarian. She currently works as a veterinary writer and consultant and has her own blog, www.vetmedbaby.com.   

Photo credit: © Todorean Gabriel E+ via Getty Images Plus  

Disclaimer: The views expressed, and topics discussed, in any NEWStat column or article are intended to inform, educate, or entertain, and do not represent an official position by the American Animal Hospital Association (AAHA) or its Board of Directors.