by Benedikt Fischer, Wayne Hall, Didier Jutras-Aswad, Bernard Le Foll – The Lancet – Volume 47. – 101141 – July 2025
For a decade, Canada, like the United States, has experienced a public health crisis from drug overdose deaths (DODs), mostly due to toxic synthetic opioids (SOs; e.g., fentanyl/analogues), commonly combined with other (e.g., methamphetamines, benzodiazepines) substances.1 This crisis has claimed >50,000 lives over the past decade in Canada alone, rendering DODs the primary population-based cause of non-natural deaths. Despite the vast implementation and expansion of prevention and treatment interventions, annual DOD tolls have steadily increased, i.e. from 2832 in 2016 to 8606 in 2023.2
Now, recent data indicate a sudden over-year decline of approximately 13% in DODs (to a projected 7501 in 2024) in Canada; this coincides with a similar approximate 17% reduction in DODs in the US.2,3 However, this development is not regionally consistent in Canada, as DOD decreases are concentrated mostly in Western/Central provinces (i.e., BC to Ontario), while Eastern provinces (e.g., Quebec) have experienced increases in DODs—regions that, notably, had reported disproportionately lower rates of SO-related DODs previously.2,4 The DOD decrease is a welcome development, yet its drivers are currently unclear while important for identification towards informing intervention development. Possibly relevant factors for consideration might include.
Risk population changes
The decline may reflect a reduction in the size of the risk population exposed to DOD risks, based on several factors. The cumulative DOD toll—mostly comprised of young/middle-aged individuals — may have substantively decimated the SO-user population.2 Its deadly consequences may have also amplified the impact of SO-related prevention messaging. In addition, restrictive policies have halved the volume of prescription opioids (i.e., 30,540 Defined Daily Doses [DDD] in 2012–2014 to 16,475 DDD in 2020–2022) in Canada, which may have reduced the population pool developing iatrogenic problems and transitioning to non-medical (e.g., SO) opioid use.
Supply dynamics
Changing SO supply dynamics may play a role. Originally, SO-products were mostly imported to North America from other source countries (e.g., China, Mexico), but there appear be shifts towards domestic production and distribution, for example as a consequence of increased production and precursor control abroad.3 Recent reports indicate increasing fentanyl production in Canada, including so-called ‘super-labs’, recently rendering it a ‘net exporter’ of fentanyl.5,6 Domestically produced fentanyl may differ in key characteristics like composition or dosing from the SOs produced abroad in ways that influence and reduce DOD-related risks.
Pharmacology
The pharmacological profiles of SOs consumed may have changed. While the vast majority of recent DODs in Canada have involved fentanyl/fentanyl-analogues, most DOD events involve other psychoactive (e.g., psychostimulant or sedative) substances either as contaminants or from concurrent use1,2 that may affect DOD-related outcomes in different ways. In the US, SO-products increasingly include xylazine, a sedative that may increase DOD risks but also extends SOs’ psychoactive effects of SOs and so may reduce use frequency and risk exposure.
Risk behaviours
Changes in DOD-relevant risk behaviours may be a factor. For example, while SO use was previously common to occur unintentionally due to distribution as counterfeit pills or mixed with other drugs, improved recognition of SO products by their consumers (e.g., through drug-checking or generally enhanced awareness) may have facilitated more cautious use practices.7 In addition, many SO consumers have switched from injecting to inhalation use, thereby reducing the DOD-related risks by decreased bio-absorption, or undertook other behaviour changes.4 However, these risk-behaviour changes have been observed for some time, and majorities of recent DODs have been shown to be associated with non-injection modes in Canada.
Interventions
In response to the toxic drug death crisis, Canadian jurisdictions have vastly expanded the availability of multiple intervention measures — such as supervised consumption, overdose prevention services, naloxone distribution and drug checking, all evidenced to contribute to DOD-related risk reductions.1,8 In addition, access to different modalities of — mostly opioid agonist-based—addiction treatment has been ramped up, also known to be protective for overdose risk.9 These expansions have occurred continuously through the DOD crisis, reducing their likelihood as a principal driver for the observed sudden DOD decrease. A more novel intervention implemented in select Canadian jurisdiction have been ‘safer drug supply’ programs which distribute pharmaceutical-grade opioids to at-risk users for DOD prevention.10 While these initiatives are documented to reduce DOD-related risk in participants, their reach in existing risk populations remains starkly limited (e.g., <5% in BC), moderating likely population-level DOD reduction effects.
Previous measures have been insufficient in curtailing the massive DOD-toll in Canada over a decade.1 The projected short-term decline in DODs is an encouraging development, though it is notably limited to only some (i.e., mostly Western/Central) regions. The tangible drivers behind the decline are not readily evident; however, similar declines in the US hint at a role of more structural (e.g., drug supply-related) factors operating across North America rather than Canada-specific determinants. The possible contributions of the factors considered, or others, should be rigorously investigated by way of robust (e.g., epidemiologic/modelling, drug toxicology, use-behavioral) examinations and analysis to guide possible development of or scaling up related further improved measures where possible towards additional, sustained reductions in the DOD toll.
Contributors
The authors jointly developed the concept for the article, and collected and interpreted related data for the study. BF led the manuscript writing; WH, DJA and BLF edited and revised the manuscript for substantive intellectual content. All authors approved the final manuscript submitted for publication.
Declaration of interests
Dr. Fischer and Dr. Jutras-Aswad have held research grants and contracts in the areas of substance use, health, policy from public funding and government organizations (i.e., public-only sources) in the last five years. Dr. Fischer acknowledges general research support from the Waypoint Centre for Mental Health Care; he was temporarily employed by Health Canada (2021–2022). Dr. Hall does not have any conflicts to declare. Dr. Jutras-Aswad acknowledges a clinical scientist career award from Fonds de Recherche du Québec (FRQS); he has received study materials from Cardiol Therapeutics for clinical trials. Dr. LeFoll has obtained research support (e.g., research funding/in-kind supports, expert consultancy, other supports) from Indivior, Indivia, Canopy Growth Corporation, ThirdBridge and Shinogi; he furthermore acknowledges general research support from CAMH, the Waypoint Centre for Mental Health Care, a clinician-scientist award from the Dept. of Family and Community Medicine and a Chair in Addiction Psychiatry from the Department of Psychiatry, University of Toronto.
Acknowledgements
The present study was not supported by any specific funder or sponsor.
References
1.
Fischer, B.
The continuous opioid death crisis in Canada: changing characteristics and implications for path options forward
Lancet Reg Health Am. 2023; 19, 100437
PubMed
Google Scholar
2.
Government of Canada
Opioid- and stimulant-related harms
Available from: https://health-infobase.canada.ca/substance-related-harms/opioids-stimulants/
Date accessed: May 15, 2025
Google Scholar
3.
Drug Policy Alliance
Fact sheet: why overdose deaths are decreasing
Available from: https://drugpolicy.org/resource/fact-sheet-health-harm-reduction-approaches-pivotal-to-decrease-in-national-drug-overdose-deaths/
Date accessed: February 5, 2025
Google Scholar
4.
Fischer, B. ∙ Robinson, T. ∙ Jutras-Aswad, D.
Three noteworthy idiosyncrasies related to Canada’s opioid-death crisis, and implications for public health-oriented interventions
Drug Alcohol Rev. 2024; 43:562-566
Crossref
Scopus (5)
PubMed
Google Scholar
5.
Financial Transactions and Analysis Report Centre of Canada
Operational Alert: laundering the proceeds of illicit synthetic opioids
His Majesty the King in Right of Canada
2025
Cat. No. FD4-39/2024E-PDF; ISBN 978-0-660-72670-0
Google Scholar
6.
CBC News
Criminal networks are shifting from fentanyl imports to Canadian-made product
2024
Available from: https://www.cbc.ca/news/politics/fentanyl-produced-in-canada-1.7275200
Date accessed: February 5, 2025
Google Scholar
7.
Brar, R. ∙ Grant, C. ∙ DeBeck, K. ∙ et al.
Changes in drug use behaviors coinciding with the emergence of illicit fentanyl among people who use drugs in Vancouver, Canada
Am J Drug Alcohol Abuse. 2020; 46:625-631
Crossref
Scopus (10)
PubMed
Google Scholar
8.
Irvine, M.A. ∙ Kuo, M. ∙ Buxton, J.A. ∙ et al.
Modelling the combined impact of interventions in averting deaths during a synthetic-opioid overdose epidemic
Addiction. 2019; 114:1602-1613
Crossref
Scopus (136)
PubMed
Google Scholar
9.
Pearce, L.A. ∙ Min, J.E. ∙ Piske, M. ∙ et al.
Opioid agonist treatment and risk of mortality during opioid overdose public health emergency: population based retrospective cohort study
BMJ. 2020; 368, m772
PubMed
Google Scholar
10.
Slaunwhite, A. ∙ Min, J.E. ∙ Palis, H. ∙ et al.
Effect of Risk Mitigation Guidance for opioid and stimulant dispensations on mortality and acute care visits during dual public health emergencies: retrospective cohort study
BMJ. 2024; 384, e076336
PubMed
Google Scholar