Public health impact and harm reduction implications of xylazine-involved overdoses: a narrative review

Abstract

Introduction Xylazine, an α2-adrenoceptor agonist sedative commonly used in veterinary medicine, is not approved for human use. Nevertheless, xylazine-involved overdose rates have surged in recent years, fueled by an increasingly toxic and synthetic illicit drug supply in North America. Methods This narrative review assessed major epidemiological trends in xylazine-involved overdoses in North America, aiming to identify harm reduction priorities. A literature search was conducted using four bibliographic databases (PubMed, Scopus, Embase, and ScienceDirect) and three preprint servers (medRxiv, bioRxiv, and Europe PMC) on May 28, 2023, to capture articles related to combinations of keywords such as “xylazine”, “opioid”, and “harm reduction”. Results Xylazine emerged as an adulterant in Puerto Rico in 2001, likely diverted from veterinary supplies. By the mid-2010s, it began proliferating across unregulated US drug markets, often contemporaneously with illicitly manufactured fentanyl (IMF), displaying characteristics of a syndemic. Initially concentrated in Northeastern regions (e.g., Philadelphia, Connecticut, Maryland), xylazine-involved overdoses later extended to the Rust Belt, Southern, and Western regions of the USA in the late 2010s and early 2020s. During this time, xylazine-involved overdoses also surged in Canada, particularly in Western provinces (British Columbia and Alberta) and Ontario with established IMF-dominated unregulated drug markets. Discussion Over the past two decades, xylazine-involved overdoses have been rapidly rising in North America and exhibit few signs of slowing down, representing a serious public health epidemic. Numerous factors may have contributed to this, including limited epidemiological surveillance and drug checking for xylazine and emerging novel adulterants; further, barriers to comprehensive, trauma-informed, non-stigmatizing treatment and social services have also exacerbated this issue. While several epidemiological and ethnographic studies have assessed these factors in the USA, limited evidence is available in Canada where xylazine emerged more recently. This underscores the need for additional research and harm reduction measures. Conclusion Harm reduction-informed public health guidelines and programs are urgently needed to promote a safer supply, strengthen the healthcare system capacity to prevent and respond to xylazine-involved overdoses, and address social and structural disparities in health outcomes.

Xylazine co-occurrence with illicit fentanyl is a growing threat in the Deep South: a retrospective study of decedent data

“…Second, more consistent testing is needed for xylazine and other concerning contaminants, and results must be conveyed to both communities and providers to inform educational initiatives and an appropriate public health response. Recent efforts to expand drug checking improve awareness of PWUD and empower them to be vigilant for substances like xylazine [ 8 , 9 ]. Implementation of these services in the Deep South is necessary.…”

“…High prevalence of xylazine in the opioid supply has been identified in many areas in the Northeast United States, first noted in Philadelphia. Other geographical regions where it has been increasingly identified include Maryland, Connecticut, and Wisconsin [ 2 , 9 ].…”

Fatal hyperpyrexia caused by xylazine: a case report

“…However, in 2001, xylazine emerged as a popular illicit drug additive in Puerto Rico ( Reyes et al, 2012 ). In the mid-2010s, it began to spread rapidly across the U.S. drug market, expanding from its initial location in the Northeast to the Rust Belt, South, and West ( Zhu, 2023 ). By 2023, the first death associated with xylazine use was reported in Europe ( Rock et al, 2023 ).…”