A 43-year-old man in the UK died in May 2022 after using a drug called xylazine, which is normally used as a large-animal tranquilizer but is now being found in heroin.
Xylazine can cause dangerous low heart rates and large open skin wounds.
The man had a history of illicit drug use and heroin, fentanyl, and cocaine were detected in his system at the time of his death, along with xylazine.
Xylazine is not approved for use in humans, and if injected directly into the bloodstream can cause open skin ulcers to form.
The drug has been causing problems in the US, and is considered an "emerging threat" due to its growing role in fatal overdoses.
There is no known safe dose of xylazine for humans, and it has been called a "flesh-eating zombie drug." The UK does not currently include xylazine in standard drug screens, so it is not known how widespread the problem is in the country.
The man's death is the first in the UK to be linked to xylazine, and it highlights the need to monitor changes in illicit drug markets and emerging drugs.