Overdoses with Xylazine and Fentanyl Recorded in Pennsylvania’s Overdose Information Network

Abstract

AbstractObjectivesThis descriptive study examined suspected xylazine co-involvement in law enforcement-recorded fentanyl overdoses in Pennsylvania (excluding Philadelphia), focusing on other drug involvement, naloxone administration, and survival.MethodsWe examined data from 10,626 suspected fentanyl-involved overdoses (95 reportedly co-involving xylazine) recorded in the Pennsylvania Overdose Information Network (ODIN), January 2018-July 2024. All measures were based on law enforcement/first-responder assessment/report. We used relative frequencies, Fisher’s exact tests, and binomial logistic regression models, comparing overdoses reportedly involving xylazine and fentanyl versus those involving fentanyl but no xylazine.ResultsSeveral drugs were reported in significantly larger proportions of overdoses in the fentanyl-xylazine group than the fentanyl-no-xylazine group: carfentanil (11.6% vs. 2.2%); other synthetic opioids (20.0% vs. 7.6%); methamphetamine (21.1% vs. 6.9%); and benzodiazepines (6.3% vs. 2.3%). Naloxone was administered in 41.1% of the cases reportedly involving xylazine, vs. 67.5% of the no-xylazine cases; 62.1% of the overdoses with xylazine recorded were fatal, compared to 27.7% of the fentanyl-no-xylazine overdoses. In multivariable regression models (among the suspected fentanyl overdoses recorded in ODIN, adjusting for age, gender, race/ethnicity, year, county, and other drugs reported): suspected xylazine involvement was associated with 65% lower odds of naloxone administration (Adjusted Odds Ratio [AOR] 0.35; 95% Confidence Interval [CI], 0.23-0.56) and 79% lower odds of survival (AOR 0.21; 95% CI, 0.13-0.35).ConclusionsIn this study of law enforcement-recorded fentanyl overdose events in Pennsylvania, excluding Philadelphia: relative to fentanyl-no-xylazine overdoses, higher proportions of xylazine-fentanyl overdoses co-involved other synthetic opioids or methamphetamine, did not receive naloxone at the scene, and were fatal.