How xylazine, a veterinary tranquilizer, is making overdoses even riskier

The latest data from the US Centers for Disease Control and Prevention shows that the country lost 105,752 lives to drug overdoses in the 12-month period ending October 2021, and while most of those overdoses involved the illicit synthetic opioid fentanyl, experts say that a veterinary tranquilizer is also leading to deaths.

Among the most concerning changes in the illicit drug market has been the appearance of xylazine, a veterinary tranquilizer also commonly known as "tranq" or "tranq dope," said Naburan Dasgupta, an epidemiologist and senior scientist at the Gillings School of Global Public Health at the University of North Carolina, Chapel Hill.

"When you look at each individual death record, when you look at the actual files and the actual chemical analysis, you see other peaks in there ... which are definitely not fentanyl and are these other contaminants that are in the drug supply," explained Dasgupta, who has been studying drug use and infectious diseases for over two decades.

According to the CDC, about half of drug overdose deaths involved multiple drugs in 2019, the most recent year for which data is available.

But detecting what drugs were involved in an overdose isn't always easy. One study of drug samples collected in Vermont and Kentucky found multiple active components in at least 89 per cent of drugs sold as opioids or cocaine.