Tranq burn: Exploring the etiology of xylazine-related soft tissue injuries

'Tranq dope' is a combination of xylazine and fentanyl that is increasingly common in the US. Frequently injected, its use appears related to severe skin and soft tissue wounds (SSTW) through an unknown mechanism. Previous research suggests that the high acidity of certain heroin source-forms contributes to vein damage and SSTW, however, the possibility of a role between the acidity of tranq dope and SSTW is understudied.

A convenience sample of persons who use drugs participated in semi-structured interviews (Philadelphia, Oct. 2023, n = 30). Observations of wounds/injection locations were made. We analyzed narrative data for perceptions of wound causation. Our partner lab analyzed the pH of 10 independently obtained samples, including tranq dope (n = 4), street opioids without xylazine (n = 2), xylazine alone (n = 2), and street stimulants (n = 2).

Observed SSTW were extraordinarily severe. Several themes emerged related to wound etiology: 1) tranq dope injection caused burning sensations; 2) vein loss occurred rapidly following uptake of tranq dope; 3) vein loss resulted in increased injection attempts, the use of large central veins (e.g., jugular and femoral), as well as more frequent 'skin-popping'; and 4) wounds (called 'tranq burn') rapidly followed vein loss. The average pH of the samples was 4, with samples containing fentanyl ranging from pH 2.1-5.9; samples containing xylazine ranging from pH 3.6-5.9; and the cocaine sample with a pH of 3.

While this study cannot confirm a causal role, our findings of reported burning sensations and moderate to high acidity of lab-tested drugs are coherent with reported rapid vein loss following initiation of tranq injection. This, in turn, lends early support to a synergistic hypothesis of tranq-related SSTW etiology: vein loss and subcutaneous injections stem from the injection of acidic drugs followed by poor tissue perfusion from vasoconstriction due to xylazine. Possible harm reduction interventions include dilution and buffering. Stigma reduction and enhanced wound care are required in harm reduction and clinical settings.