Dangerous 'tranq dope' detected in Alberta as supply spreads across North America

Over the past few years, Health Canada has been tracking the spread of xylazine, an animal tranquilizer, in the country's street drugs. Informally, it's often referred to as "tranq dope" or just the "zombie drug."

Lethbridge overdose site has seen a fair bit of the 'zombie drug' in recent weeks

Pills are pictured in a person's hand.
An individual with a drug testing facility takes samples from a patron in Vancouver in this file photo. Xylazine, an animal tranquilizer often used for horses, is making its way into the drug supply across Canada. (The Canadian Press)

Over the past few years, Health Canada has been tracking the spread of xylazine, an animal tranquilizer, in the country's street drugs. Informally, it's often referred to as "tranq dope" or just the "zombie drug."

Xylazine is not approved for human use but increasingly has been cut with opioids like fentanyl, which can lead to gruesome effects. Users can sometimes fall into blackout states and develop agonizing wounds and "rotting flesh" that can require amputation.

Its effects cannot be reversed by naloxone, the life-saving, overdose-reversal medication, making an already deadly opioid crisis even more dire.

In recent months, the number of seized street drug samples testing positive for the tranquilizer has been alarming in Ontario and British Columbia.

Jurisdictions across North America have been monitoring the spread closely.

On Wednesday, the U.S. Office of National Drug Control Policy designated xylazine as an "emerging threat," having been detected in almost all 50 states.

A woman stands in front of lockers.
Rebecca Haines-Saah, an associate professor at the University of Calgary's Cumming School of Medicine, says the growing emergence of 'tranq dope' has serious implications, especially when it comes to wound care. (Rebecca Haines-Saah)

In Alberta, the tranquilizer was detected 34 times in 2022, compared with 1,011 in Ontario and 260 times in British Columbia. Still, one public health expert feels the threat hasn't been sufficiently communicated in this province.

"When we see these issues pop up in other jurisdictions, it's really just a matter of time," said Rebecca Haines-Saah, an associate professor at the University of Calgary's Cumming School of Medicine. 

"The problem is that the illicit markets are so flexible and adaptable. And things proliferate much faster than our response can. And there's always a hesitancy to get ahead of things."

Tranquilizer being detected

The University of Calgary operates an email drug alert site through the U of C web servers, which shares information by zone. Haines-Saah shared a recent alert sent out at the end of March from an overdose prevention site in Lethbridge with CBC News.

"[We're] seeing a fair bit of xylazine right now," reads the notice.

In the notice, the centre's manager writes that naloxone had been ineffective as a medical response to those with xylazine in their systems, and that users show slow recovery times and are incredibly tired through recovery.

Last month, the drug was also suspected to have emerged on the Blood Reserve, west of Lethbridge.

Reserve officials said that while they had seen xylazine in the area previously, "new and serious side-effects" had started to emerge.

"[There are] stroke-like symptoms where people may seem OK one moment and then have severe symptoms thereafter," reads a notice posted by the reserve. 

"Blackout states that last for hours can occur, which leave people vulnerable to harm when they are not aware what is occurring around them."

WATCH | Canadian street drugs laced with toxic animal tranquillizer: 

More street drugs being laced with toxic animal tranquillizer

1 year ago
Duration 2:38
A dangerous animal tranquillizer called xylazine is increasingly finding its way into the illegal drug supply, Health Canada data shows. The drug can cause serious side effects and is resistant to naloxone, the fast-acting medication that can reverse opioid overdoses.

The fact that naloxone is ineffective against xylazine has made the drug an emerging concern for those who work with the homeless population in Calgary.

"But I don't think it's just specific to xylazine. I think that we just have an issue with an unregulated drug supply, period," said Amy Leung, manager of clinical services for CUPS, a social services agency in Calgary. 

"A lot of the time people think that they're purchasing fentanyl, but there might be benzodiazepines in there … we call them adulterants that are being added to their opioids, oftentimes without their knowledge."

An 'emerging threat'

In Calgary, the presence of xylazine was first detected in 2015, the Calgary Police Service says. In 2022, five samples were returned from testing that contained xylazine, and there have been two positive samples returned so far this year.

"The effects of xylazine and the fact that naloxone doesn't have the ability to reverse them are concerning. As we see new drugs and drug combinations make it into the community, we remain vigilant on their spread and consumption, and respond accordingly," wrote a CPS spokesperson in a statement.

Alberta recorded 1,630 drug-poisoning deaths (including all substances) in 2022, the second-worst year since the province started collecting data in 2016.

The Office of the Chief Medical Examiner reported low concentrations of xylazine in 43 deaths since January 2019, all of which also involved fentanyl.

A sign in a window says Naloxone here and has an illustration of a nasal spray.
Naloxone, which is used to reverse opioid overdoses, is ineffective against xylazine. (Cara Nickerson/CBC)

When asked what the Alberta strategy was in dealing with xylazine, Colin Aitchison, a spokesperson with the province's Mental Health and Addiction Ministry, said in a statement it was important "to be clear that all illicit drugs should always be considered dangerous and potentially deadly."

Aitchison also cited various provincial initiatives geared toward addressing the opioid crisis, including the province's plan to build recovery communities and expand access to opioid agonist therapy, which refers to the use of medications like naloxone and methadone.

Given that naloxone is ineffective against xylazine, CBC News requested more information as to whether programs offering safer supply might be considered should Alberta see an influx of xylazine similar to other jurisdictions across North America.

Aitchison said Albertans could access the Virtual Opioid Dependency Program or narcotic transition services.

"The solution to the addiction crisis is not simply providing more drugs to people with addiction without any controls or engagement in a treatment program," he wrote regarding a safer supply.

He noted the government believes that as the availability of opioids increases in the community, so does the potential harm.

Haines-Saah, meanwhile, said a safe supply isn't about making opioids more available but about replacing a deadly supply for those at high risk of overdose and death.


Joel is a reporter/editor with CBC Calgary. In fall 2021, he spent time with CBC's bureau in Lethbridge. He was previously the editor of the Airdrie City View and Rocky View Weekly newspapers. He hails from Swift Current, Sask. Reach him by email at