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

This study explored whether law enforcement/first responder-reported fentanyl overdose response actions (such as administration of the opioid overdose reversal agent naloxone) differed between overdoses in which xylazine was, versus was not, suspected to be co-involved. Data were drawn from the Pennsylvania State Police's Overdose Information Network (ODIN) for 11,478 suspected fentanyl-involved overdoses, 137 reportedly co-involving xylazine, recorded across Pennsylvania, excluding Philadelphia, January 2018-January 16, 2025. We used relative frequencies, Fisher's exact tests, and binomial logistic regression to compare first responders' overdose response actions in suspected fentanyl overdoses cases in which xylazine was, versus was not, reportedly co-involved. Naloxone was administered at the scene of 46.0% of the overdoses reportedly involving fentanyl and xylazine, vs. 67.3% of the reported fentanyl-no-xylazine overdoses. Multivariable regression results (among the suspected fentanyl overdoses in ODIN, adjusting for age, sex, race/ethnicity, year, county rurality, and other drugs suspected to be involved) indicated that suspected xylazine co-involvement was associated with 60% lower odds of naloxone administration (Adjusted Odds Ratio, 0.40; 95% Confidence Interval, 0.28-0.57). Observed differences in overdose response based on suspected xylazine co-involvement support the importance of equipping first responders with the tools and training to recognize/manage the distinct challenges of xylazine-fentanyl-involved overdose.