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A class of drugs commonly used to treat sleep and anxiety disorders is increasingly being found in the illicit opioid supply, raising the risk of overdose, producing complex overdoses that are more difficult to reverse and rendering medications used to treat substance use disorders ineffective in some cases.

Benzodiazepine adulteration of illicit opioids has been documented on occasion in the past, but researchers in British Columbia said an increase in mid-2018, when benzodiazepines were detected in 6.3 per cent of 543 samples sent for confirmatory testing over a 15-month period, is believed to be the first “sizable outbreak” of its kind during the opioid overdose epidemic.

Since then, drug-checking services across Canada have detected benzodiazepines in half or more of samples expected to be opioids, with adulteration increasing significantly during the pandemic.

Karen Ward, a drug policy adviser to the City of Vancouver, theorizes that benzodiazepines have saturated the market because they are cheap, readily available and can stretch out a supply of fentanyl without watering it down with fillers such as caffeine. But they can reduce opioid tolerance and increase the risk of overdose – particularly in the context of a toxic drug crisis with extreme concentrations of fentanyl in the mix.

“People are very, very susceptible to overdose,” Ms. Ward said. “We are living in a fundamentally different era with synthetics.”

Benzodiazepines act on the same receptors as alcohol and can produce similar effects, such as memory loss, slurred speech and an unstable gait. Ingesting a combination of opioids and benzodiazepines – commonly called “benzo dope” – can increase the risk of respiratory depression, which can be fatal.

Naloxone should still be administered to reverse the effects of an opioid overdose, but the medication does not work on benzodiazepines, so an overdose victim can remain unconscious for hours or come to and behave erratically, remembering almost nothing when the effect passes.

Post-mortem toxicology testing in both B.C. and Ontario has detected benzodiazepines in about a third of drug deaths during the pandemic. The BC Coroners Service notes that the detection rate increased from 15 per cent last July to 49 per cent in January. The Office of the Chief Coroner for Ontario added that detection of etizolam, a benzodiazepine analogue, has increased from 7.9 per cent to 13.8 per cent in opioid-related deaths.

The Vancouver Island Drug Checking Project, which tested 117 samples in January, found benzodiazepines or etizolam in half the samples expected to be opioids. Meanwhile, Toronto’s drug-checking service has detected benzodiazepine-related drugs in more than 75 per cent of 690 expected fentanyl samples in the past six months.

Front-line workers in Alberta who spoke with The Globe and Mail have also reported atypical overdose presentations, but there are no drug-checking services available to the public in the province.

Bruce Wallace, a co-principal investigator for the Vancouver Island Drug Checking Project, said this latest development shows that the overdose crisis is “not just about fentanyl. It’s about the supply being unregulated and criminalized, which is making it unpredictable and now increasingly variable and complex.”

Karen McDonald, the lead for Toronto’s drug-checking service at St. Michael’s Hospital, said that 20 of the expected fentanyl samples checked over the past two months were associated with overdoses; of those, 18 contained fentanyl and at least one benzodiazepine-related drug.

She said her service is working with clinical partners to study the changing drug supply, but that an unregulated market can change on a dime.

“What happens tomorrow if suddenly benzos were out and something else was in?” Ms. McDonald said. “A number of people, I’m sure, would be suffering because they had been using fent with benzos in it for the past year and their bodies are potentially dependent on it.”

Keith Ahamad, an addiction physician in Vancouver, said the adulteration has rendered treatment medications such as methadone and buprenorphine-naloxone (Suboxone) ineffective for some, often leaving physicians to figure out how to stabilize patients when the available tools no longer work.

“Without a regulated drug supply, it’s almost impossible to know what is causing the withdrawal symptom currently,” he said. “Is it added benzodiazepines? High concentrations of fentanyl? Withdrawal syndromes overlap and have distinct features, but the people using drugs uniformly feel terrible. I see people regularly reaching for substances they wouldn’t have used before to try and feel better – often, a lot more alcohol, which can be even more dangerous.”

When Madeline Grant injected benzo dope for the first time, regret hit as fast as the drugs. The man who had given it to her had tried in vain to get her to leave the overdose prevention site and use elsewhere. She understood why when she regained consciousness.

“Obviously he had ulterior motives,” said Ms. Grant, who came to more than five hours later, scared but not physically harmed. “I couldn’t remember a thing. I felt really vulnerable because of the state of my life at the time – not having money and taking dope from someone – and I was angry at myself.”

But while many ingest the combination unknowingly, Ms. Grant said there’s no shortage of people seeking it out.

“They want it because their lives are in turmoil,” she said. “They don’t want to go through the day penniless. They don’t want to remember their lives. They don’t want to feel pain. So they’ll buy that dope that puts them to sleep for 10 hours.”

Ms. Ward has also unintentionally ingested benzodiazepines. The most recent instance happened this past weekend, when she smoked what she thought was rock cocaine and suddenly became exceedingly tired. She nodded off, coming to for only a minute at a time every few hours for the next day.

She described the drug as extremely potent and completely unlike taking an extra clonazepam, a regulated benzodiazepine prescribed to treat anxiety and panic disorders.

“At least I didn’t die,” she said. “It’s become a reality to think like that. It crosses people’s minds every time that they use, this nihilistic, ‘We’ll see. I hope I don’t die.’”

The Dalke and Seibel families share a tragic connection: Both lost a child to opioids. Now they plead with others to steer clear of illicit drugs, and to get help for mental illness if possible. Preliminary numbers show 5,233 Canadians died of opioid-related toxicity in 2020, the deadliest year since national tracking began.

The Globe and Mail

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