Medetomidine is a non-opioid sedative (Central Nervous System [CNS] depressant) approved for use in Canada in veterinary medicine, Its effects are similar to those of xylazine but is about 200 times more potent.
While the most intense alerts are currently in BC, similar contaminants have been detected in street drugs in other parts of Canada
In late 2025, health authorities in British Columbia (BC) began issuing a series of urgent drug advisories after detecting an increasingly dangerous veterinary sedative — medetomidine (meh-deh-TOH-mih-deen) — in unregulated street drugs, particularly those sold as the drug fentanyl or “down.”
This presence represents a serious public health and social concern that worsens the province’s ongoing toxic drug crisis.
Medetomidine is a non-opioid sedative (Central Nervous System [CNS] depressant) approved for use in Canada in veterinary medicine to sedate animals like dogs and cats. It depresses the central nervous system and cardiovascular function.
The drug is not approved for human use. Its effects are similar to those of xylazine (used by veterinarians as a sedative, muscle relaxant, and analgesic for large animals such as horses and cattle), but it’s about 200 times more potent.
Over the past year, drugs seized and checked in communities across BC have increasingly tested positive for medetomidine mixed with fentanyl, benzodiazepines, or other illicit substances. Health authorities are warning that this combination creates complex drug poisoning profiles that are harder to treat and more dangerous for users.
KEY RISKS INCLUDE:
Deep, prolonged sedation — beyond what is expected from opioids alone.
Low or unmeasurable pulse and slow breathing, which increases the risk of fatal overdose
Naloxone (Narcan) won’t fully reverse the effect, cause medetomidine is not an opioid.
Prolonged unresponsiveness, which can last hours even if breathing continues.
This is especially dangerous because many people who use drugs expect naloxone to reverse any overdose. Still, with medetomidine involvement, breathing can return, yet deep sedation persists — requiring advanced supportive care.
In November 2025, BC saw a record number of 911 calls for suspected toxic drug poisonings. Public health officials linked the surge to fentanyl contaminated with medetomidine, which caused unusually deep and prolonged non-opioid sedation in overdose cases.
Recent toxic drug advisories were issued in the Fraser Health Region, Northern Health & First Nations Health Authority, as well as in Vancouver Coastal Health Notices. Warnings about medetomidine in street drugs and advising caution, even when naloxone is administered
The appearance of medetomidine in the unregulated supply touches many.
IT TOUCHES BROADER SOCIAL HEALTH CONCERNS LIKE:
Increased Overdose and Death Risk: People who use drugs are more likely to experience unpredictable sedation and poisoning. Traditional harm reduction tools like naloxone may help with opioid effects, but not with the sedation caused by medetomidine — challenging first responders and communities.
Strain on Health Services, Emergency departments and harm reduction services are reporting more complex cases requiring prolonged monitoring and care, often with limited resources.
Community Fear and Misinformation
For individuals, families, and communities affected by substance use, the presence of an unknown and potent sedative creates fear, mistrust, and uncertainty — especially when drug contents are unknowable without testing.
In response to this crisis,
HEALTH AUTHORITIES RECOMMEND:
The National Overdose Response Service are also recommended for people who may be using alone.
While the most intense alerts are currently in BC, similar contaminants have been detected in street drugs in other parts of Canada, prompting nationwide concern about drug supply safety and unpredictable adulterants.
The toxic drug crisis remains a focus of public health efforts across provinces, with medetomidine representing part of a larger pattern of dangerous, unregulated additives.
Medetomidine’s infiltration into the unregulated drug market has become a significant social health concern in British Columbia and parts of Canada. The combination of deep sedation, limited responsiveness to naloxone, and unpredictable effects demands increased public awareness, harm reduction services, and community preparedness.
Addressing this issue requires collaboration between health systems, community groups, and people with lived experience to reduce harm and protect lives.
Author,
Addiction Field Specialist,
Referral & Consultation Counsellor, Ethics in Practice – NAADAC
Reviewed by Susan Chubbs Certified Drug and Alcohol Treatment Specialist