Xylazine Detection and Involvement in Drug Overdose Deaths — United States, 2019

Xylazine is a drug used in veterinary medicine as an animal sedative with muscle relaxant and analgesic properties

1. It is not approved by the Food and Drug Administration for use in humans, in whom it acts as a central nervous system depressant and can cause respiratory depression, slowed heart rate, and hypotension
2. When used as a toxic adulterant in illicitly produced opioids such as fentanyl or heroin
3. Xylazine might potentiate sedation and respiratory depression, increasing the risk for fatal overdose. In addition, because xylazine is not an opioid, it does not respond to opioid reversal agents such as naloxone; therefore, if illicit opioid products containing xylazine are used, naloxone might be less effective in fully reversing an overdose.