News How xylazine – a tranquilizer showing up in fentanyl – makes it harder to slow overdose deaths April 4, 2023Ken Alltucker, USA TODAYComments Off on How xylazine – a tranquilizer showing up in fentanyl – makes it harder to slow overdose deaths Xylazine, known as the street drug tranq or zombie heroin, is increasingly being found in fentanyl and heroin. It's known to cause open wounds.