A rise in the circulation of highly potent fentanyl that is increasingly being mixed with other drugs is making Canada’s street drug supply so toxic and unpredictable, tools to prevent overdoses such as naloxone are not always fully effective, experts say.
The situation has become so volatile, front-line doctors and workers say they are left to guess at what mixture of substances a person in crisis may have been exposed to, which is why they say Canada needs to move faster on measures like safe supply and drug regulation to stop the sharp rise in opioid-related deaths in Canada.
Since 2021, powerful sedatives such as benzodiazepines are more frequently being identified in street-purchased opioids, often unbeknownst to those taking the drugs, according to the Canadian Centre for Substance Use and Addiction.
Benzodiazepines do not respond to naloxone, also known as Narcan — a medication used to reverse the effects of opioids that has become a critical tool for first responders and those on the front lines of Canada’s growing opioid crisis.
It means people who overdose on opioids mixed with benzodiazepines are harder and more complex to treat, says 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.
“What that means is that you’re seeing overdoses that are longer and more drawn out and potentially a little bit more difficult to manage, especially outside of the hospital,” he said.
“It can mean (a situation) where somebody might need a dose of Narcan then a trip to the hospital and be OK within an hour or two, or it may take many hours for them to recover from those benzos. Certainly, for people who use drugs and for front-line workers, it’s really scary.”
Why is mixing drugs so dangerous?
Tara Gomes, a scientist at Unity Health Toronto and director of the Ontario Drug Policy Research Network, says the increasing unpredictability in the drug supply in Canada poses challenges for community-based programs that help people who use drugs, as they are not set up to handle the longer-term care that may be required to aid someone overdosing from opioids mixed with benzos.
“They’re able to administer naloxone, and the person might be OK … but they are not able to be roused and people within those programs have to help monitor that person might have to stay open later or make sure there are people around because this person might need a couple of hours before they’re fully aroused and can leave the program,” Gomes said.
“It adds all levels of complexity in terms of overdose response, but also the kinds of tools and supports that programs need to be able to provide to people when they’re having to deal with this challenge.”
Bach says benzodiazepines are being found in up to 30 per cent of street opioids in B.C.
In Toronto, benzos were found in about 44 per cent of fentanyl samples tested by the Toronto Drug Testing Service in 2022.
But the unresponsiveness to naloxone is only the “tip of the iceberg” when it comes to the harms of this deadly cocktail of drugs, Bach said.
People who unknowingly take opioids cut with benzos can black out for hours or even days, he said, which can result in significant harms for those who may be highly vulnerable or marginalized.
“It makes you very, very susceptible to robbery, sexual assault or just or just waking up in a really unsafe situation,” Bach said.
“It does lead to increased risk of overdose and it makes the treatment of patients, both as far as treating their acute withdrawal and helping them stabilize, and helping those who are trying to access our treatment really challenging because there’s a whole variety of substances involved and because neither they nor I really know what they’ve been using. So we end up having to guess.”
This guessing game is being made even more challenging due to an increase in the potency of the fentanyl currently circulating in Canada.
A number of stronger analogues, or alternate formulations, of fentanyl have been showing up in street drugs across the country, particularly in B.C., Alberta and Ontario, which is adding to the toxicity of the unregulated supply, Gomes said.
It has become a particular problem since the COVID-19 pandemic began, according to the federal data. Experts say border closures during the height of pandemic disrupted many established drug trafficking routes, which led to changes in the drug supply.
“As different fentanyl, like carfentanil, for example, enter into the drug supply, you can be exposed to a much higher effective dose of the opioid than you might have been used to,” Gomes said.
“That unpredictability of how strong the drug supply is with opioids can be dangerous. But also, when you start mixing in other drugs, that can be really dangerous as well.”
Karen McDonald, who leads Toronto’s Drug Checking Service, says recent samples have identified drug mixtures that include nitazene opioids and carfentanil, which are 10 and 100 times stronger than fentanyl, respectively.
“We’ve been up and running since October of 2019. And since that time, we are increasingly seeing the supply just get worse and worse,” she said.
The increased presence of these more highly potent opioids is also having a negative impact on the effectiveness of naloxone as an antidote, she added.
“What we’re seeing is that, as more potent or stronger opioids enter the supply, it’s taking more naloxone to reverse overdoses.”
Animal tranquilizer xylazine prompts warnings
Both McDonald and Gomes also registered concern about contamination of Canada’s street drug supply with other compounds, such as a newly circulating animal tranquillizer called xylazine, which can cause severe necrotic skin ulcers, according to the U.S. Food and Drug Administration (FDA).
The presence of xylazine in opioids in the United States prompted a warning from the FDA in November 2022, alerting health-care professionals to “increasing reports of serious side effects” from the drug, known as “tranq.”
The warning noted the tranquillizer, normally used in veterinary medicine, could be contained in illicit drugs such as fentanyl and heroin.
The Canadian Community Epidemiology Network on Drug Use issued its own alert last July identifying the emerging presence of xylazine in a small number of opioid samples tested in B.C., Manitoba, Ontario, Quebec and Nova Scotia.
Since then, its presence in Canada has grown, according to drug test samples and coroner’s reports in B.C. and Ontario.
“I think it’s just another marker of the fact that this supply is so unpredictable…. That’s what’s so dangerous about it,” Gomes said.
“It’s not only the individual substances we’re seeing, but the fact that nobody really knows what they’re getting.”
That’s why she is among a growing number of experts calling for larger-scale access to programs such as safe supply.
Increase in toxic drugs strengthens case for safe supply
The federal government funds 17 safe supply pilot projects in four provinces, where clients are given prescriptions of pharmaceutical-grade opioids.
But only a few thousand Canadians have access to these programs, Gomes said.
“We need to be able to provide this kind of response to everybody who needs it and not just a few people in a couple of urban centres around the country,” she said, adding that better low-barrier access to other forms of substance use treatments is also needed.
Governments in Canada have adopted an approach to regulate alcohol and cannabis, even though these are drugs that can cause harm and addiction, she noted.
These substances are regulated so people can know what they’re getting and not have to rely on an unpredictable black market, Gomes said.
“There seems to be this challenge for people going to that next level with other substances like opioids,” she said.
“The alternative, if you’re saying you don’t want to provide people with a safe option for these substances, is to say we’re OK with letting people die, we’re OK with saying, ‘You’ve got to just take what you can get and hope for the best.’
“Personally, that’s not something that I’m OK with.”
Doris Payer, an addiction neuroscience expert and knowledge broker for the Canadian Centre on Substance Use and Addiction, says it’s not just people who habitually use drugs and those who are addicted who are at risk from these substances.
Casual or experimental users face the same risks of overdose or death from the unpredictable cocktail of substances circulating within Canada’s street drug supply, she said, which is why regulation of these substances should be part of the conversation.
“If it’s an unregulated drug supply issue, then one of the answers is let people know what’s in the substances that they’re taking. They have a right to be aware of what they’re putting in their bodies,” Payer said.
“It makes harm reduction services like supervised consumption sites make more sense and it makes the conversation about a safer supply make a lot more sense because if, ultimately, it’s the toxicity of the supply that’s driving this problem, then finding a way to regulate the supply is the obvious answer.”
Bach says short- and long-term solutions are needed to address the growing toxicity of Canada’s drug supply, including safe supply as well as better supports for those experiencing poverty, homelessness and mental health issues.
He called on governments to treat the toxicity in the unregulated market like the crisis it has become.
A total of 32,632 Canadians died due to opioids between 2016 and June of 2022, according to the latest federal data.
That includes 3,556 people who died from opioid toxicity in the first six months of 2022 — which means 20 Canadians died of toxic opioids every day last year.
“We need a response from all sectors that’s commensurate with the scale of the damage we have seen,” Bach said.
“We saw it with COVID-19, we saw what can happen if everyone decides to take action to try and reduce the number of deaths … but we’ve yet to see a response of that scale for the overdose crisis, even though we’re in her seventh year and we’re losing six people in my province every single day.”