Xylazine-induced acute skin necrosis in two patients who inject fentanyl

To the Editor: Xylazine is an alpha-2-agonist traditionally used in veterinary settings to sedate horses.1 However, there are increasing reports of xylazine-laced fentanyl in the United States.2-4 We report 2 patients with skin necrosis localized to sites of fentanyl injection. Given the increasing prevalence of xylazine in fentanyl, dermatologists need to recognize xylazine-induced skin changes in patients with active fentanyl use.