
A tranquilizer used for animals is appearing more frequently in street drugs across North America, alarming drug policy experts and harm reduction advocates alike. Xylazine may sound like the name of a "Star Trek" character, but it's actually a muscle relaxer widely used in veterinary medicine – and it's causing big problems across the continent.
Xylazine has found its way into what used to be the U.S. heroin supply but is now almost entirely illicit fentanyl, a powerful opioid that can be 100 times more potent than morphine. Xylazine is not an opioid, but it can knock a user out for longer than most opioids – about six to eight hours – thus playing a growing role in drug overdose deaths, according to experts.