Health Canada says it is receiving a growing number of illegal drug samples containing xylazine – a veterinary sedative, relaxant and painkiller not approved for human use.
According to a report by the federal agency, the animal tranquilizer began appearing as an additive to opioids and cocaine in 2019 and is most commonly mixed with fentanyl. Normally prescribed for dogs, cats, horses and cattle, xylazine can act as a central nervous and respiratory system depressant.
“It can cause a dangerous drop in blood pressure and heart rate, and when taken with other depressants like opioids, it increases your risk of overdose,” said Samuel Tobias, a doctoral student at BC. Center for Substance Use.
Health Canada’s report compiled illicit drug samples submitted by law enforcement agencies across the country to the agency’s Drug Analysis Service (DAS). The health agency says the data may not be completely representative of drug seizures and substances on the market.
Across Canada, data shows that the number of xylazine identifications has increased from 205 in 2019 to 2,324 in 2022.
British Columbia accounts for 21.2% of these samples and has seen the number of samples containing xylazine quadruple, from 58 in 2019 to 260 in 2022.
In a statement to CBC, Health Canada said xylazine has “also been detected in a proportion of opioid-related deaths.”
Health Canada points out that overdose reversal medications like naloxone are less effective on those who have taken xylazine.
Tobias explained that xylazine is not an opioid, which means that naloxone – an opioid antagonist – is not able to counter it.
“If someone has taken a lot of xylazine that causes them to be in a lowered state of consciousness, using naloxone isn’t going to wake them up,” Tobias said.
Benzodiazepines contaminate BC drugs more often
Tobias says xylazine isn’t as common as other fentanyl additives like benzodiazepines, accounting for less than 5% of opioid samples under drug control.
“The prevalence of xylazine in samples has increased slightly over the past year and we’ve seen more in the past three months, but it’s still below 5% of samples checked,” Tobias said.
Still, Tobias cautions against consuming the drug due to possible extreme side effects and increased risk of overdose.
Along with drops in blood pressure and slow heart rate, Tobias also cites significant tissue damage, fainting and memory loss.
“Wounds [from damaged tissue] are large and, if deep enough, can sometimes require the amputation of the legs,” Tobias said.
Tobias says extreme side effects have mostly been seen in places like Philadelphia and Puerto Rico, where xylazine is more common.
Tobias says the unpredictability of the unregulated drug supply can be deadly and advises getting all illicit drugs tested.
“For people who rely on an unregulated drug supply, drug verification services are one of the ways people can find out what’s in their supply before they consume it,” said Tobias.