Did xylazine, a horse tranquilizer used as a medication, cause deaths in Colorado?

Since the beginning of 2022, there have been at least four deaths related to the drug xylazine in Colorado.

Xylazine is an animal tranquilizer used in horses that has the same sedative effects as opioids. It is not approved for human use.

As an illegal drug, it gained widespread popularity in Puerto Rico in the early 2000s. In the United States, it is most heavily used illegally in the northeastern United States.

State health officials said some fentanyl users use the drug to prolong the effects of fentanyl and prevent withdrawal. The drug affects the central nervous system, causing drowsiness, amnesia, and low blood pressure. Because xylazine acts like a sedative, it is difficult to tell if someone has overdosed on opioids. There is no known antidote.

Fentanyl overdoses killed at least 920 people in Colorado in 2022 and 1,087 in 2023.

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