Tranq Burn: the acidity of xylazine and fentanyl combinations

Project Summary Severe skin and soft tissue wounds are the most visible consequence of the use of xylazine (a non-FDA-approved animal tranquilizer) in combination with the synthetic opioid fentanyl – a combination known as “Tranq.” Still, the mechanism by which Tranq contributes to these wounds remains unclear. This project proposes to use qualitative and quantitative means to investigate the potential that the causticity, i.e., the acidity of this drug combination, contributes to rapid venous loss and the development of Tranq-related wounds. The qualitative portion of this study will utilize a rapid assessment protocol in two locations (Philadelphia, PA; Lynn, MA) alongside an ongoing longer-term ethnographic project being conducted in San Francisco, CA. Rapid assessment ethnography is particularly useful for gleaning insights into emerging health problems. Semi-structured interviews and observation of drug preparation and use will help to triangulate quantitative findings from the street- and lab-based pH testing. During interviews conducted with people using xylazine-contaminated fentanyl, we will explore the perceived role played by variations in the prevalence of xylazine in fentanyl, polydrug combinations with xylazine- fentanyl and other drugs, e.g., cocaine and methamphetamine, route of administration, and injection site in the development of xylazine-related wounds. Additionally, the team will measure street drug sample acidity with a portable digital pH meter while observing real-world drug preparation methods. Alongside street-based measurements, pH analyses will be run by a professional toxicology laboratory on 25 high-quality samples from each research location. Qualitative analysis of these samples will be performed utilizing gas chromatography-mass spectrometry and liquid chromatography quadrupole time-of-flight mass spectrometry. In addition, samples with enough mass will be aliquoted for quantitative analysis conducted by gas chromatography-mass spectrometry using a directed scope that includes fentanyl, xylazine, and other substances, with results reported as a weight-by-weight percent. Observations of street drug preparation techniques will inform the laboratory measurement of sample pH, where complete xylazine-fentanyl samples from study locations will be prepared commensurate with real-world conditions and measured using a lab-grade meter. Applying actual drug preparation techniques observed from the street to laboratory samples will further validate street-based findings.