"In overdose data from 10 jurisdictions – representing all four major US census regions – xylazine was found to be increasingly present in overdose mortality (Fig. 1). The highest prevalence was observed in Philadelphia, (with xylazine present in 25.8% of overdose deaths in 2020), followed by Maryland (19.3% in 2021) and Connecticut (10.2% in 2020). In 2021, xylazine prevalence also grew substantially in Jefferson County, Alabama, reaching 8.4% of overdose fatalities. Across the four census regions, the Northeast had the highest prevalence, and the West had the lowest (Fig. 2), with only six xylazine-present overdose deaths in total detected in Phoenix, Arizona, and 1 in San Diego County, California. Across jurisdictions, a clear increasing trend was noted. Pooling data for 2015, a total xylazine prevalence of 0.36% was observed. By 2020, this had grown to 6.7% of overdose deaths, representing a 20-fold increase. From 2019–2020 – the last year of data available for all jurisdictions – the prevalence increased by 44.8%."

Source

Friedman, J., Montero, F., Bourgois, P., Wahbi, R., Dye, D., Goodman-Meza, D., & Shover, C. (2022). Xylazine spreads across the US: A growing component of the increasingly synthetic and polysubstance overdose crisis. Drug and alcohol dependence, 233, 109380. doi.org/10.1016/j.drugalcdep.2022.109380.