Xylazine moves from the stables to the streets

Photo: Todorean Gabriel/Adobe Stock

As a veterinarian, you may know xylazine as Rompun, Sedazine or AnaSed. Known for its long-acting sedative effects, xylazine is frequently used in veterinary medicine as a tranquilizer and often in combination with ketamine for anesthesia as well as sedation, muscle relaxation, and analgesia.

On the streets, however, xylazine is known by a variety of other names. These nicknames include “Tranq”, “Tranq Dope”, “Sleep Cut”, and “Anestesia De Caballo” (Horse Anesthesia) as well as “Zombie Drug”.

Addiction among us

A drive through the Kensington neighborhood in Philadelphia shows how much xylazine-laced opioid addiction has taken over. Addicted individuals can be seen lying unresponsive on the ground and others nodding off or walking around aimlessly uncoordinated and out of step.

According to a December 2022 health update released by the Philadelphia Department of Public Health, xylazine is now the most common adulterant in the Philadelphia illicit drug supply chain.¹ In addition, data released by the DEAreported that, in 2021, xylazine was found in more than 90% of heroin and fentanyl samples in Philadelphia.²

And it’s not just Philadelphia. Drug Enforcement Administration (DEA) laboratory data also revealed xylazine to be the most commonly found substance in “polydrug” mixtures with fentanyl.According to the CDC and state and local officials now tracking the threat, other mid-Atlantic cities, including New York City, are experiencing the same horrors. Findings from DEA’s laboratory system between 2020 and 2021 indicate the influx of xylazine in all 4 US census regions. Although the northeast has the highest total (some of the hardest hit states being Connecticut, Maryland, Massachusetts, Rhode Island, and Vermont), each of the 4 regions has seen an increase in identifications of xylazine, with the south reflecting the most significant increase (193% increase in xylazine instances over the 2-year period), followed by the West with an almost 112% increase.²

On March 20, 2023, the DEA released a Public Safety Alert wherein DEA Administrator Ann Milgram stated, “Xylazine is making the deadliest drug threat our country has ever faced, fentanyl, even deadlier.” Milgram also noted that the agency “has seized xylazine and fentanyl mixtures in 48 of 50 States.” The DEA Laboratory System is reporting that in 2022 approximately 23% of fentanyl powder and 7% of fentanyl pills seized by the DEA contained xylazine.”³

The xylazine factor

As a long-acting sedative, xylazine can be mixed with opioids like fentanyl to lengthen its euphoric effects. As an unscheduled substance, xylazine is also more easily accessible than other adulterants used as a cutting agent and is less likely to lead to scrutiny from law enforcement agencies. At a cost of $6-$20 per kilogram, readily available for purchase online, the use of xylazine as an opioid adulterant increases the volume of product that can be produced in a polydrug mixture; reducing the amount of fentanyl or heroin being used while also increasing net profit for illicit drug traffickers.

The zombie effects

As a drug, xylazine’s main effect is heavy sedation, which can last up to 6 hours. Blackouts induced by xylazine use can leave individuals in a zombie-like unconscious state for hours, with dangerously low blood pressure levels and heart rates. When xylazine users “come to”, the opioid high has long since faded and they immediately crave more. Xylazine users have been reportedly compelled to begin searching for their next “hit” while still under the influence demonstrating aggressive behavior and uncoordinated movements…hence the “zombie effect”.

But, perhaps the most compelling reason xylazine has earned the name “zombie drug” is because of the wounds it creates. Human use of xylazine—whether injecting, snorting, smoking, or swallowing the drug—leads to the development of severe skin, muscle, nerve, and soft tissue wounds known as eschars. Unlike scabs made up of dried blood cells and fluids that sit on top of the skin, eschars are a collection of dead tissue within a wound that are flush within the skin surface, highly persistent, and easily infected. Eschar patches of rotting tissue may form anywhere and when left untreated can lead to necrosis, amputation, and other serious life-threatening conditions.

Unlike the opioids it is commonly used as an adulterant in so-called polydrug mixtures with, xylazine is a sedative. Xylazine also has no approved antidote for human use and is resistant to typical opioid overdose reversal agents such as naloxone. This makes overdoses associated with xylazine more difficult to identify as they appear similar to opioid overdoses and are often not included in routine drug screening tests. Consequently, the presence of xylazine may render naloxone noneffective or less effective.

A count of xylazine-positive overdose deaths in the US is not currently possible, as not all jurisdictions routinely conduct testing for xylazine in postmortem toxicology. Testing procedures can vary even within the same state. Additionally, it is not currently included with the CDC reporting of national statistics on fatal overdoses. As a result, it is highly likely the prevalence of xylazine is widely underestimated.

Point of care testing for xylazine is not yet available. Therefore, individuals who use substances may not be aware that they have been exposed to xylazine. If an individual does not respond to naloxone, overdose responders should continue to provide supportive care, such as airway management and supplemental oxygen, to patients with prolonged sedation in the presence of normal respirations.

Combatting xylazine

On February 28, 2023, the FDA announced that it was taking action to restrict the unlawful entry of xylazine active pharmaceutical ingredients and finished dosage form drug products into the United States.⁴ This agency’s action was taken in response to the growing public health concern that xylazine has created and aims to prevent xylazine from further entering the US market for illicit purposes, while still maintaining availability for legitimate uses in animals.

As part of the newly enacted actions, the FDA will halt and review xylazine shipments to ensure they're headed toward state-licensed pharmacies, agency-approved manufacturing facilities, or veterinarians, who use the drug for licit purposes. Although not a total fix, it’s a start.

State controls

Beyond federal controls, certain states are enacting their own controls on xylazine. In New York, Xylazine has been a schedule III-controlled substance depressant since 2017.⁵ On January 11, 2023, the Indiana General Assembly proposed a bill8 for toxicology screening at the time of a person’s death. This bill proposed that if a coroner reasonably suspects the cause of the person's death to be overdose of an opioid or if the person was administered an overdose intervention drug prior to death and was unresponsive to the overdose intervention drug, the coroner shall test certain bodily fluids to determine whether the they contain any amount of xylazine.⁶

On February 9, 2023, Illinois’ State Senate introduced a billseeking to amend the Illinois Controlled Substance Act and make xylazine a schedule I controlled substance.⁷ Additionally, on February 17, 2023, Illinois’ State House proposed a bill to further make Xylazine’s isomers, esters, ethers, salts, and salts of isomers, esters, and ethers, a schedule II-controlled substance.⁸

With congressional lawmakers considering scheduling xylazine through legislation, concerns have been raised regarding how moving this drug to a federally scheduled controlled substance list will impact the industry and the use of it as a therapy in veterinary medicine. On the flip side, concerns are being raised about the impact on human health and addiction if xylazine remains an unregulated and unmonitored substance.

Conclusion

It is unlikely that the illicit use of xylazine will ever completely go away or be eliminated. By becoming educated about the problem, aware about how to handle it, and proactive in approach, we have the ability to not only survive but also do our part to prevent new threats like xylazine from taking over. Veterinarians and their teams must be aware of the issues discussed above and recognize that they can help keep the xylazine-induced zombie apocalypse from taking over.

About the author: Kelley Detweiler is a DEA regulatory compliance expert who provides controlled-substance risk-management solutions to veterinarians through her partnership with Dr Peter Weinstein in Simple Solutions 4 Vets Inc. Kelley has spoken on international platforms including the United Nations and is the coauthor of "Safeguarding Controlled Substances" published by the American Animal Hospital Association. Contact: kelley@simplesolutionsforvets.com.

References

1. Cheryl Bettigole, MD, MPH, ANDREW BEST, DPA, LCSW, DANIEL TEIXEIRA DA SILVA MD, MSHP. Xylazine (Tranq) Exposure Among People Who Use Substances in Philadelphia. Philadelphia Department of Public Health. Published December 8, 2022. Accessed March 10, 2023. https://hip.phila.gov/document/3154/PDPH-HAN_Update_13_Xylazine_12.08.2022.pdf/.
2. DEA Joint Intelligence Report. The Growing Threat of Xylazine and its Mixture with Illicit Drugs. Drug Enforcement Administration. Published October 2022. Accessed March 8, 2023. https://www.dea.gov/sites/default/files/2022-12/The%20Growing%20Threat%20of%20Xylazine%20and%20its%20Mixture%20with%20Illicit%20Drugs.pdf.
3. Public Safety Alert: DEA Reports Widespread Threat of Fentanyl Mixed with Xylazine. Drug Enforcement Administration. Published March 20, 2023. Accessed March 20, 2023. https://www.dea.gov/alert/dea-reports-widespread-threat-fentanyl-mixed-xylazine.
4. FDA Takes Action to Restrict Unlawful Import of Xylazine. FDA. Published February 28, 2023. Accessed March 10, 2023. https://www.fda.gov/news-events/press-announcements/fda-takes-action-restrict-unlawful-import-xylazine.
5. Sen. Terrence Murphy. Senate Bill S7397. New York State Senate website. https://www.nysenate.gov/legislation/bills/2015/S7397. Published April 27, 2016. Accessed March 10, 2023.
6. Meltzer, Lauer, Vermilion, Garcia Wilburn. HB1286. Indiana General Assembly. Updated February 14, 2023. Accessed March 8, 2023. https://in-proxy.openstates.org/2023/bills/HB1286/versions/HB1286.02.COMH. Published January 11, 2023.
7. Sen. Patrick J. Joyce. SB2089. Illinois General Assembly. Updated March 10, 2023. Accessed March 10, 2023. https://ilga.gov/legislation/BillStatus.asp?DocTypeID=SB&DocNum=2089&GAID=17&SessionID=112&LegID=146962.
8. Rep. Jackie Haas. HB3873. Illinois General Assembly. Published February 17, 2023. Accessed March 8, 2023. https://www.ilga.gov/legislation/BillStatus.asp?DocNum=3873&GAID=17&DocTypeID=HB&SessionID=112&GA=103.