Notes From the Field: Xylazine-Related Deaths - Cook County, Illinois, 2017-2021

Xylazine awareness and attitudes among people who use drugs in Ohio, 2023-2024

BACKGROUND

The prevalence of xylazine, a non-opioid tranquilizer not for human consumption, in illicitly manufactured fentanyl is increasing in the United States. However, little is known about xylazine awareness and attitudes among people who use drugs.

METHODS

A cross-sectional survey of people who use drugs in Ohio was conducted from November 2023 - May 2024 to identify xylazine awareness and attitudes in rural and urban counties across the state. Study participants were recruited from naloxone distribution sites, including health departments, syringe service programs, and community-based organizations.

RESULTS

Among 630 people who use drugs in Ohio, more than one-half (53.5%) were unaware of xylazine being in "street drugs," regardless of urbanicity. Among individuals who were aware of xylazine, most (73.0%) indicated they did not want to use the drug and try to avoid it. In addition, 75.8% of this group felt it was "very" or "extremely" important to know if xylazine was in their drugs.

DISCUSSION

This research found that many people who use drugs in Ohio are unaware of xylazine and its risks. An important finding of this study is that most individuals who had heard of xylazine did not want to use it and were concerned about knowing whether xylazine was in their drugs.

Modeling Changes of Fatal Xylazine-Involved Drug Overdoses in Connecticut Across Time

BACKGROUND

Fatal drug overdoses have involved both xylazine and fentanyl. Xylazine is a non-opioid substance used in veterinary medicine. This study aimed to model changes in fatal xylazine-involved drug overdose deaths from 2019 to 2023 in Connecticut using overdose death data from the Office of the Chief Medical Examiner.

METHODS

Xylazine-involved drug overdose fatality rates were calculated by number of deaths per year per 100,000 population from 2019 to 2023. We used joinpoint regression modeling to evaluate quarterly overdose rates across age, number of drugs, and drug types with a significance level of p < 0.05.

RESULTS

From 2019 to 2023, there were 1116 xylazine-involved fatal overdoses with a cumulative rate of 31.3 deaths per 100,000. Xylazine-involved overdose death rates were significantly higher in Hispanic populations compared to both non-Hispanic White and Black populations (p < 0.05). The joinpoint analyses showed that xylazine-fentanyl mortality rates significantly increased by 0.18 per 100,000 per quarter from 2019 to 2022. Xylazine-fentanyl overdoses involving at least 4 or 5 substances significantly increased. Windham, Hartford, New London, and New Haven counties had the highest xylazine-involved death rates.

CONCLUSION

Xylazine-fentanyl deaths increased from 2019 to 2023, and often involved multiple substances (e.g., cocaine, ethanol, benzodiazepines, and oxycodone). Results show Hispanic populations, those aged 35-49, and 50+ experienced high rates of xylazine-fentanyl overdose deaths. Vulnerable populations in Connecticut for special consideration for future intervention and local resource allocation are recommended.

Accessibility of Naloxone in Pharmacies Registered Under the Illinois Standing Order

Introduction

To expand access to naloxone, the state of Illinois implemented a standing order allowing registered pharmacies to dispense the drug without an individual prescription. To participate under the standing order, pharmacies were required to opt in through a formal registration process. In our study we aimed to evaluate the availability and price of naloxone at registered pharmacies.

Methods

This was a prospective, de-identified, cross-sectional telephone survey. Trained interviewers posed as potential customers and used a standardized script to determine the availability of naloxone between February-December, 2019. The primary outcome was defined as a pharmacy indicating it carried naloxone, currently had naloxone in stock, and was able to dispense it without an individual prescription.

Results

Of 948 registered pharmacies, 886 (93.5%) were successfully contacted. Of those, 792 (83.4%) carried naloxone, 659 (74.4%) had naloxone in stock, and 472 (53.3%) allowed purchase without a prescription. Naloxone nasal spray (86.4%) was the formulation most commonly stocked. Chain pharmacies were more likely to carry naloxone (adjusted odds ratio [aOR] 3.16, 95% confidence interval [CI] 1.97-5.01, P < 0.01) and have naloxone in stock (aOR 2.72, 95% CI 1.76-4.20, P < 0.01), but no more likely to dispense it without a prescription. Pharmacies in higher population areas (aOR 0.99, 95% CI 0.99-0.99, P < 0.05) and rural areas adjacent to metropolitan areas (aOR 0.5, 95% CI 025-0.98, P < 0.05) were less likely to have naloxone available without a prescription. Associations of naloxone availability based on other urbanicity designations, overdose count, and overdose rate were not significant.

Conclusion

Among pharmacies in Illinois that formally registered to dispense naloxone without a prescription, the availability of naloxone remains limited. Additional interventions may be needed to maximize the potential impact of a statewide standing order.

Xylazine is an agonist at kappa opioid receptors and exhibits sex-specific responses to opioid antagonism

Xylazine is in the unregulated drug supply at increasing rates, usually combined with fentanyl, necessitating understanding of its pharmacology. Despite commentary from politicians, and public health officials, it is unknown how xylazine impacts naloxone efficacy, and. few studies have examined it alone. Here, we examine the impact of xylazine alone and in combination with fentanyl on several behaviors in mice. Surprisingly, naloxone precipitates withdrawal from xylazine and fentanyl/xylazine coadministration, with enhanced sensitivity in females. Further, xylazine is a full agonist at kappa opioid receptors, a potential mechanism for its naloxone sensitivity. Finally, we demonstrate surprising effects of xylazine to kappa opioid antagonism, which are relevant for public health considerations. These data address an ongoing health crisis and will help inform critical policy and healthcare decisions.

Xylazine-Associated Wounds and Related Health Concerns Among People Who Use Drugs: Reports From Front-Line Health Workers in 7 US States

BACKGROUND

Xylazine, an adrenergic alpha-2 agonist increasingly present in the US drug supply, is associated with severe skin ulcers and other harms. Expert knowledge from front-line harm reduction and healthcare professionals is an essential component of evidence-based practice. The purpose of this study is to describe the progression and treatment of xylazine-associated wounds, other xylazine-related health concerns, and the most urgent research priorities as reported by front-line harm reduction and healthcare professionals serving people who use drugs.

METHODS

A convenience sample of 17 healthcare and harm reduction professionals who serve people who use drugs in the US states of Maryland, Massachusetts, Michigan, Minnesota, North Carolina, Pennsylvania, and Texas participated in semi-structured interviews. Participants were asked about the appearance and progression of xylazine-associated wounds; preferred treatment strategies; other xylazine-related harms experienced by people who use drugs; and the most urgent priorities for xylazine-related research.

FINDINGS

Xylazine-associated wounds were broadly described as small lesions appearing mostly on extremities both at and away from injection sites, often within hours or days of exposure, that quickly developed into large, complex, chronic wounds. Reported risk of secondary infection was generally low but appeared more common among unhoused populations. Most participants preferred conservative treatment strategies that included regular wound care, enzymatic debridement, and hygiene. Xylazine-associated wounds and xylazine withdrawal reportedly act as significant barriers to care, including addiction treatment. Participants reported urgent need for scientific research and evidence-based guidance on the management of xylazine-associated wounds and withdrawal.

CONCLUSIONS

High-quality scientific evidence on risk factors for xylazine-associated wounds and on their biologic mechanisms is needed. Such studies could inform new strategies for the prevention and treatment of these wounds. Efforts to improve the management of xylazine withdrawal and to reduce stigma by incorporating harm reduction professionals into healthcare settings may improve access to and retention in care.

Loneliness and fearfulness are associated with non-fatal drug overdose among people who inject drugs

BACKGROUND

People who inject drugs (PWID) experience high rates of drug overdose death with the risk of mortality increasing after each non-fatal event. Racial differences exist in drug overdose rates, with higher rates among Black people who use drugs. Psychological factors may predict drug overdose.

METHODS

Cross-sectional data from a survey administered to PWID in Baltimore, MD enrolled in a social network-based intervention were analyzed. Linear regression methods with generalized estimating equations were used to analyze data from indexes and network members to assess for psychological factors significantly associated with self-reported number of lifetime drug overdoses. Factors associated with number of overdoses were assessed separately by race.

RESULTS

Among 111 PWID enrolled between January 2018 and January 2019, 25.2% were female, 65.7% were Black, 98.2% reported use of substances in addition to opioids, and the mean age was 49.0 ± 8.3 years. Seventy-five individuals (67.6%) had a history of any overdose with a mean of 5.0 ± 9.7 lifetime overdoses reported. Reports of feeling fearful (β = 9.74, P = 0.001) or feeling lonely all of the time (β = 5.62, P = 0.033) were independently associated with number of drug overdoses. In analyses disaggregated by race, only the most severe degree of fearfulness or loneliness was associated with overdose among Black participants, whereas among White participants, any degree of fearfulness or loneliness was associated with overdose.

CONCLUSIONS

In this study of PWID loneliness and fearfulness were significantly related to the number of reported overdose events. These factors could be targeted in future interventions.

Reported xylazine exposure highly associated with overdose outcomes in a rapid community assessment among people who inject drugs in Baltimore

BACKGROUND

Addressing xylazine harms are now a critical harm reduction priority, but relatively little epidemiological information exists to determine prevalence, magnitude, and correlates of xylazine use or related outcomes.

METHODS

We conducted a rapid behavioral survey among people who inject drugs (n = 96) in Baltimore November-December 2022. Using a novel indicator of self-reported presumed xylazine effects, we examined prevalence and sociodemographic correlates of past year presumed xylazine effects and association with overdose and wound-related outcomes. Chi-square and descriptive statistics were used to examine bivariate associations overall and separately for those who reported xylazine by name and by reported fentanyl use frequency.

RESULTS

Almost two-thirds (61.5%) reported experiencing xylazine effects. There were no differences by socio-demographics, but xylazine effects were more commonly reported among those who reported injecting alone (66% vs 38%%, p < 0.007) and daily fentanyl use (47% vs 24% p < 0.003). Those reporting xylazine exposure was three times as likely to report overdose (32% vs 11%, p < 0.03) and twice as likely to have used naloxone (78% vs 46%, p < 0.003). They also more commonly reported knowing someone who died of an overdose (92% vs 76%, p < 0.09) and to report an abscess requiring medical attention (36% vs 19%, p < 0.80). These associations were higher among respondents who specifically named xylazine and those who used fentanyl more frequently, but fentanyl frequency did not fully explain the heightened associations with xylazine effects.

CONCLUSIONS

This study provides insight into the scope of xylazine exposure and associated health concerns among community-based PWID and suggests measures that may be instrumental for urgently needed research.

Fentanyl Exposure and Detection Strategies Utilized by Clinical Trial Participants Seeking Linkage to Opioid Use Disorder Treatment at a Syringe Service Program

INTRODUCTION

The USA continues to face a fentanyl-driven overdose epidemic. Prior research has demonstrated users of illicit opioids are concerned about fentanyl exposure and overdose, but the strategies they report using to detect fentanyl's presence lack empirical support. This study compares self-report and biologically detected fentanyl use and investigates overdose risk and risk reduction behaviors among a sample of high-risk people who use opioids.

METHODS

Structured enrollment interviews conducted as part of a larger clinical trial assessed self-reported fentanyl exposure as well as strategies used to determine believed fentanyl exposure and prevent overdose among 240 participants enrolled at a Chicago, IL syringe service program. Urinalysis measured actual fentanyl exposure.

RESULTS

Most participants identified as African American (66.7%) and had considerable overdose experience (76.7% lifetime and 48% in the past year). Most also tested positive for fentanyl (93.75%) despite reporting no past year use of fentanyl or fentanyl-adulterated drugs (64.17%). The most utilized approaches reported for identifying fentanyl exposure were stronger effects of the drug (60.7%), sight or taste (46.9%), and being told by someone using the same drugs (34.2%). Few participants (14%) reported using fentanyl test strips. No significant associations were identified between self-report and urinalysis measures or urinalysis results and risk reduction strategies.

CONCLUSION

This study adds to prior fentanyl exposure risk research. The disconnect between participants' fentanyl detection methods and reported overdose experiences supports the need for more research to identify and understand factors driving access and use of overdose prevention resources and strategies.

Evaluation of the relationship of xylazine and fentanyl blood concentrations among fentanyl-associated fatalities

INTRODUCTION

Illicit fentanyl and fentanyl-analogs have produced a devastating increase in opioid fatalities in the United States. Increasingly, xylazine has been found in the illicit fentanyl supply. The role of xylazine in fentanyl intoxication remains unclear. We reviewed coroner records to evaluate trends and effects associated with xylazine in fentanyl-related fatalities.

METHODS

This is a retrospective cohort study of all deaths reported to the Franklin County Coroner's Office in Ohio from 1 January 2019 to 16 March 2023, in which fentanyl was determined causative or contributory to death. Cases identified as fentanyl-associated fatalities were separated into two groups based on whether or not xylazine was also detected.

RESULTS

There were 3,052 fentanyl-related fatalities during the study period. 4.8 percent of these decedents also tested positive for xylazine. There was no meaningful demographic difference between fentanyl-related fatalities in which xylazine was detected versus those without xylazine detected. There was a mean of 726 fentanyl-associated fatalities per year, with a peak of 846 deaths in 2020 and a decline thereafter. The percentage of fentanyl-related fatalities with xylazine detected increased in linear fashion from 2.7 percent in 2019 to 6.6 percent in 2022. The median fentanyl concentration was 17.0 µg/L (inter-quartile range: 7.9, 27.0) in cases with xylazine detected and 10.0 µg/L (inter-quartile range: 5.6, 18.0) without xylazine. The odds of a fentanyl concentration greater than 40 µg/L in cases with xylazine detected was more than twice as great (odds ratio: 2.41; 95 percent confidence interval: 1.58-3.64) than that in cases without xylazine detected.

CONCLUSIONS

Postmortem fentanyl concentrations were greater in cases with xylazine detected than those without xylazine detected. Though it is unclear why patients who were exposed to xylazine tolerated higher opioid doses prior to succumbing to death, we postulate that xylazine may act to competitively antagonize some degree of mu-opioid receptor binding by opioids.

Comparative toxicology of syringe exchange and postmortem blood samples in the District of Columbia: Trends and affinity analysis

This cross-sectional analysis aimed to understand the similarities and differences between drugs detected in syringes collected from syringe service providers in the District of Columbia and fatal overdose deaths captured by the State Unintentional Drug Overdose Reporting System. Substance exposures for these fatal and non-fatal drug use outcomes have not been previously compared. Substance distributions were examined and a paired significance test was used to compare changes over time. Affinity analysis was employed to reveal substance co-occurrences. Between September 2020 and September 2022, 1,118 postmortem blood samples (PBSs) and 3,646 syringes exchange samples (SESs) were processed, with fatal overdoses increasing 24.1%. Polysubstance use was more commonly found in postmortem blood (82.5%) than in syringe samples (48.6%). Of samples containing opioids, 94.8% of blood samples and 86.3% of syringes contained fentanyl, fentanyl analogs or fentanyl precursors/metabolites. PBSs had double the frequency of co-occurring stimulants and opioids (43.9%) as SESs (21.8%). Major changes in occurrence frequency over time were found for opioid and stimulant exposure in both groups, especially in the increased occurrence of fluorofentanyl (>400%), methamphetamine (>90%) and xylazine (>60%), while the incidence of fentanyl, heroin and metabolite morphine declined. These results indicate that while fatal use and syringe exchange populations have distinct substance exposures, which may contribute to differences in mortality rate, their substance distributions have similar change magnitudes. This study highlights the utility of using multiple data sources to provide a comprehensive description of drug use patterns and discusses the limitations in reporting data from each source.

Identification of the veterinary sedative medetomidine in combination with opioids and xylazine in Maryland

Public health, public safety, and forensic science personnel continue to face the emergence of new compounds into the drug market. While focus is often put on the detection of new analogs of known illicit drugs, monitoring the changes in cutting agents and other compounds can be equally as important. Over the last year, near real-time monitoring of the drug supply in Maryland has been completed through a public health-public safety partnership whereby residue from suspected drug packaging or used paraphernalia is collected and analyzed. Through this project, we have recently detected the presence of the veterinary sedative medetomidine in a small number of samples. The presence of medetomidine has been identified in both public health and law enforcement samples and in the presence of fentanyl and xylazine-another veterinary sedative that has been widely observed over the last year. While the rate at which medetomidine has been detected remains low, it is concerning and worthy of continued monitoring.

Widespread Distribution of Xylazine Detected Throughout the United States in Healthcare Patient Samples

OBJECTIVES

Xylazine is a tranquilizer commonly added into the illicit drug supply and a likely contributor to overdoses because it does not respond to naloxone reversal. The objective of this study was to perform a retrospective data analysis on xylazine-positive samples collected from patients in various outpatient healthcare settings to illustrate geographic distribution and common copositive substances, which may also contribute to risk of adverse events.

METHODS

Samples for which providers ordered testing for xylazine were subjected to enzymatic hydrolysis, extracted, and analyzed using liquid chromatography-tandem mass spectrometry. Retrospective analysis was performed on xylazine-positive samples collected from April 2021 to March 2022, to include geographic location and copositive substances.

RESULTS

Xylazine was identified in 413 of 59,498 samples from adults aged 20-73 years and originated from 25 of the 39 states where xylazine testing was ordered. The most common routine substances detected with xylazine were fentanyl, buprenorphine, naloxone, cocaine, d -methamphetamine, and delta-9-tetrahydrocannabinol. The most common designer drugs detected included fentanyl analogs, isotonitazene, and designer benzodiazepines.

CONCLUSIONS

Xylazine is geographically spread throughout the United States, indicative of a wide incorporation into the illicit drug supply. These findings differ from previous studies in that these samples originated from healthcare providers in routine care settings, where other reports typically involve overdose deaths. This analysis illustrates that routine testing for xylazine in outpatient settings can afford providers the opportunity to educate individuals and adjust harm reduction measures to potentially mitigate overdose risk.

Xylazine-involved fatal overdoses and localized geographic clustering: Cook County, IL, 2019-2022

BACKGROUND

Xylazine, a veterinary analgesic sedative, is circulating in the illicit drug markets of at least 23 states including Illinois. We conducted a geographic analysis to better identify the spatial distribution of xylazine-involved fatal overdoses in Cook County, IL.

METHODS

Cook County Medical Examiner Office's (CCMEO) publicly available data was used to identify xylazine-involved fatal overdoses from January 1, 2019, to June 30, 2022. Xylazine-positive (cases) to xylazine-negative groups with drug mixtures involving fentanyl, alcohol and stimulants (controls) were matched on age, race, sex, and year of death. Ripley's K-function was used to examine the likelihood of case clustering compared to controls with the Bernoulli spatial scan deployed to identify specific geographic clusters.

RESULTS

Almost all (94.4%) xylazine-positive overdoses contained fentanyl. Using coordinate-based matching, we found that approximately 3% of xylazine overdose incidents were co-located with other overdoses. Xylazine cases clustered to from 0 to 16.1 miles (max=10.6 miles). Results of the Bernoulli spatial scan varied by control group with two high-risk clusters found relative to alcohol and stimulants and a low-risk cluster relative to fentanyl. Differences in co-occurring drugs were found between xylazine and fentanyl groups like the absolute number of drugs (4.6v 3.4, p<0.0001) and fentanyl analog types.

CONCLUSIONS

Xylazine fatal overdose incident locations exhibited localized clustering relative to fentanyl overdoses but clusters were not precisely detected at these scales. Even so, our results, especially relative to repeat overdose micro "hot spots", offer insight on targeting harm reduction and other services at the neighborhood-level.

Opioid overdoses involving xylazine in emergency department patients: a multicenter study

INTRODUCTION

Illicit opioids, consisting largely of fentanyl, novel synthetic opioids, and adulterants, are the primary cause of drug overdose fatality in the United States. Xylazine, an alpha-2 adrenergic agonist and veterinary tranquilizer, is being increasingly detected among decedents following illicit opioid overdose. Clinical outcomes in non-fatal overdose involving xylazine are unexplored. Therefore, among emergency department patients with illicit opioid overdose, we evaluated clinical outcome differences for patients with and without xylazine exposures.

METHODS

This multicenter, prospective cohort study enrolled adult patients with opioid overdose who presented to one of nine United States emergency departments between 21 September 2020, and 17 August 2021. Patients with opioid overdose were screened and included if they tested positive for an illicit opioid (heroin, fentanyl, fentanyl analog, or novel synthetic opioid) or xylazine. Patient serum was analyzed via liquid chromatography quadrupole time-of-flight mass spectroscopy to detect current illicit opioids, novel synthetic opioids, xylazine and adulterants. Overdose severity surrogate outcomes were: (a) cardiac arrest requiring cardiopulmonary resuscitation (primary); and (b) coma within 4 h of arrival (secondary).

RESULTS

Three hundred and twenty-one patients met inclusion criteria: 90 tested positive for xylazine and 231 were negative. The primary outcome occurred in 37 patients, and the secondary outcome occurred in 111 patients. Using multivariable regression analysis, patients positive for xylazine had significantly lower adjusted odds of cardiac arrest (adjusted OR 0.30, 95% CI 0.10-0.92) and coma (adjusted OR 0.52, 95% CI 0.29-0.94).

CONCLUSIONS

In this large multicenter cohort, cardiac arrest and coma in emergency department patients with illicit opioid overdose were significantly less severe in those testing positive for xylazine.