In recent months, xylazine, a potent sedative circulating in the illicit drug supply in the United States, has been increasingly detected in Canada’s street drugs, as health experts have raised concerns due to its risk of contributing to overdose-related deaths.
Xylazine is an animal tranquilizer and analgesic used in veterinary medicine and, specifically, on large animals. Furthermore, the increasing incidence of xylazine being detected in opioids in various parts of the U.S. led to a warning released by the FDA in November 2022, alerting health-care professionals to “increasing reports of serious side effects” from the drug, also referred to as “tranq.”
According to data released by Substance Use Philadelphia, xylazine has been found in over 90% of opioid-containing drug samples tested in Philadelphia in 2021.
In July of 2022, the Canadian Community Epidemiology Network on Drug Use (CCENDU) issued an alert after detecting xylazine in opioid samples tested in B.C., Manitoba, Ontario, Quebec, and Nova Scotia. In recent months, the number of illicit drug samples testing positive for xylazine has increased, and it has been linked to a number of overdose-related deaths, as shown by coroner’s reports in B.C. and Ontario.
Due to its sedative effects, xylazine can result in central nervous system depression, respiratory depression, and even death. Importantly, naloxone, a drug that can be used to reverse the effects of opioid overdose, is ineffective in countering the effects of xylazine.
According to Karen McDonald, the lead for Toronto’s Drug Checking Service, xylazine first appeared in Canada’s illicit opioid supply in September 2020, but since then, its presence has augmented.
In addition, McDonald added that most people who end up with xylazine in their fentanyl are not aware of its presence. “Our understanding was that most folks in Toronto were not choosing to use xylazine, it was just kind of being cut into their drugs unknowingly. So it certainly is a problem,” she added.
In his interview with Global News, Dr. Paxton Bach, an addiction medicine specialist at St. Paul’s Hospital in Vancouver and the co-medical director of the BC Centre on Substance Use, said xylazine has been increasingly appearing in British Columbia’s drug supply. “The effects of that in a drug supply are still not fully known. But it leads to the increasing unpredictability of any given sample of drugs and can lead to really profound effects for people who are using the drugs — blackouts, loss of memory and other medical consequences,” he said.
In a communication released by the Public Health Agency of Canada (PHAC), xylazine was detected in 198 drug samples from six provinces in 2020, with the majority of these detected in B.C. and Alberta. In 2022, it was found in over 2,000 drug samples in eight provinces and one territory, including over 1,400 detections in Ontario, which corresponds an increase of over 950% over three years.
“Xylazine has also been detected in a proportion of opioid related deaths,” said Charlaine Sleiman, a spokesperson for PHAC and Health Canada. “Health Canada is currently evaluating the risks of xylazine in order to determine if further regulatory action is needed.”