Xylazine detected in unregulated opioids and drug administration equipment in Toronto, Canada: clinical and social implications

Abstract

Background The North American opioid overdose crisis is driven in large part by the presence of unknown psychoactive adulterants in the dynamic, unregulated drug supply. We herein report the first detection of the psychoactive veterinary compound xylazine in Toronto, the largest urban center in Canada, by the city’s drug checking service. Methods Toronto’s Drug Checking Service launched in October 2019. Between then and February 2021, 2263 samples were submitted for analysis. The service is offered voluntarily at harm reduction agencies that include supervised consumption services. Samples were analyzed using gas chromatography–mass spectrometry or liquid chromatography-high resolution mass spectrometry. Targeted and/or untargeted screens for psychoactive substances were undertaken. Results In September 2020, xylazine was first detected by Toronto’s Drug Checking Service. Among samples analyzed from September 2020 to February 2021 expected to contain fentanyl in isolation (610) or in combination with methamphetamine (16), xylazine was detected in 46 samples (7.2% and 12.5% of samples, respectively). Samples were predominantly drawn from used drug equipment. Three of the samples containing xylazine (6.5%) were associated with an overdose. Conclusion We present the first detection of xylazine in Toronto, North America’s fourth-largest metropolitan area. The increased risk of overdose associated with use of xylazine and its detection within our setting highlights the importance of drug checking services in supporting rapid responses to the emergence of potentially harmful adulterants. These data also highlight the clinical challenges presented by the dynamic nature of unregulated drug markets and the concomitant need to establish regulatory structures to reduce their contribution to overdose morbidity and mortality.

Rising abuse of veterinary drugs

“…17 Early administration of naloxone may reverse the opioid sedation effect and avoid intubation; however, endotracheal intubation and mechanical ventilation may be required in severe cases. 8 Obtain an arterial blood gas evaluation or venous blood gas measurement in addition to pulse oximetry or co-oximetry to assess for hypoxia and adequacy of ventilation. Obtain a fingerstick blood glucose level to exclude hypoglycemia, especially in patients with serious and persistent respiratory depression.…”

“…Xylazine is used for recreational purposes as an adulterate in cocaine, fentanyl, heroin, and methamphetamine to enhance their effectiveness or to increase street value by increasing the net weight of the product. When added to fentanyl or heroin, xylazine potentiates sedation and respiratory depression, increasing the risk of a fatal overdose 5,6,8,11,12. The State Unintentional Drug Overdose Reporting System reported 45,676 overdose deaths in 2019.…”

“…Hemodialysis is ineffective for xylazine due to its large volume of distribution 8. Extended hospital observation may be warranted due to prolonged signs and symptoms 5,6,8…”

Overdose Prevention and Housing: a Qualitative Study Examining Drug Use, Overdose Risk, and Access to Safer Supply in Permanent Supportive Housing in Vancouver, Canada

“…In 2021, the Canadian province of British Columbia (BC) reported an illicit drug toxicity (overdose) mortality rate of almost 43 deaths per 100,000 persons (up from 34.3 deaths per 100,000 in 2020), with 83% involving illicit fentanyl [2]. While the overdose crisis is fueled by an unregulated lethal drug supply -including increasing adulteration with novel substances like etizolam and xylazine [3,4] -growing evidence demonstrates the relationship between housing and overdose risk [5][6][7][8][9][10][11][12]. For instance, in BC, 84% of overdose deaths in 2021 occurred indoors (56% in private residences, and 28% in other private locations including social and supportive housing), with the most recent statistics for 2022 showing near identical patterns [2].…”

Moving towards a continuum of safer supply options for people who use drugs: A qualitative study exploring national perspectives on safer supply among professional stakeholders in Canada

“…Canada is in the midst of a public health emergency, with 24,626 opioid toxicity deaths reported between January 2016 and June 2021, accounting for 19.1 deaths per 100,000 individuals [ 1 ]. Contamination and toxicity of the unregulated drug supply is fueling the overdose epidemic, with 87% of accidental apparent opioid toxicity deaths involving fentanyl [ 1 ], and increasing detection of benzodiazepines such as etizolam and other psychoactive compounds such as xylazine [ 2 , 3 ]. The crisis has widespread consequences, including being one of the leading causes of accidental death [ 4 ] and contributing to a decline in life expectancy [ 5 , 6 ].…”