"Xylazine is currently not a scheduled substance under the United States Controlled Substances Act, though some efforts are underway to change this (Drug Enforcement Administration, 2021; Murphy, n.d.). However, supply side efforts to control xylazine adulteration of fentanyl/heroin are unlikely to work and – similar to trends seen when trying to decrease the availability of alcohol, cannabis, and cocaine – will likely exacerbate adulteration (Cowan, 1986). Xylazine test strips, by contrast, are a demand-driven response to unwanted adulterants and may be able influence the composition of the drug supply if xylazine is linked to specific stamps (i.e., how fentanyl/heroin products are branded in Philadelphia) (Friedman et al., 2022). This new form of drug checking represents a potential tool to further empower PWUD to make informed choices about what and how they consume drugs.

"All participants who spontaneously discussed wanting xylazine test strips, or were asked if they would want them, indicated they would use them to test their fentanyl/heroin before drug consumption, if available. Xylazine test strips are not currently available and, to our knowledge, are not in development. Research is needed from broader monitoring and analysis of the drug supply to determine whether xylazine in fentanyl/heroin is pharmaceutical grade. Additionally, it is important to understand if a xylazine test strip would be capable of detecting any xylazine analogs.

"A xylazine test strip may have the potential to positively impact drug use in a similar manner to fentanyl test strips. Fentanyl test strips have been found to significantly alter drug use behavior and foster safer drug use practices with continued testing. Individuals using fentanyl test strips prior to drug use did so in order to prevent fentanyl overdose and the potential need for emergency interventions (Peiper et al., 2019). Additionally, there have been studies reporting fentanyl test strip use following drug use. Among these individuals, positive results for fentanyl were associated with use of reduced doses on subsequent drug consumption occasions (Karamouzian et al., 2018)."


Reed, M. K., Imperato, N. S., Bowles, J. M., Salcedo, V. J., Guth, A., & Rising, K. L. (2022). Perspectives of people in Philadelphia who use fentanyl/heroin adulterated with the animal tranquilizer xylazine; Making a case for xylazine test strips. Drug and alcohol dependence reports, 4, 100074. doi.org/10.1016/j.dadr.2022.100074.