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. 2023 Jul-Aug;17(4):468-470.
doi: 10.1097/ADM.0000000000001132. Epub 2023 Jan 6.

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

Andrew C Holt  1 , David M Schwope, Kathy Le, Joshua P Schrecker, Rebecca Heltsley
Affiliations

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

Andrew C Holt et al. J Addict Med. 2023 Jul-Aug.

Abstract

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.

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Conflict of interest statement

The authors were employed by the Aegis Sciences Corporation for the duration of the study period (ACH, DMS, JPS, RH) or a student on clinical clerkship as part of the Doctor of Pharmacy curriculum (KL). There are no other conflicts, including relevant financial interests, activities, relationships, or affiliations to report.

Figures

Figure 1
Figure 1
States where xylazine testing has been ordered and detection status.
See this image and copyright information in PMC

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