What makes Canada’s illegal drug supply dangerous?

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For nearly a decade, Canada has been experiencing a public health crisis of drug toxicity (overdose) deaths and related harms. This crisis has been devastating — nearly 50,000 people have died since 2016.1 Each person was someone with a unique story, dreams, family, friends and other loved ones. The primary driver of drug toxicity deaths is drugs from the illegal, unregulated supply, which has become increasingly dangerous in recent years. 

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This article explores how dangerous changes in the illegal drug supply came about. It also explains why the unpredictable strength and contents of illegal drugs make them so dangerous and discusses the implications for service providers.

What is the illegal, unregulated drug supply?

The illegal drug supply consists of the various unregulated sources or markets where drugs are produced, distributed, bought and sold. The drugs in this supply are illegal because of prohibition. Prohibition refers to laws and policies that ban the production, transportation, sale and possession of certain drugs. The federal Controlled Drugs and Substances Act is the primary law that makes drugs illegal in Canada. Globally, governments spend billions of dollars a year enforcing prohibition,2 but illegal markets continue to thrive.3 In illegal drug markets, there are no rules or regulations to ensure products are safe for consumers. This may sound obvious; a market that operates outside the law cannot be made to follow rules. For over a century, drug laws have prioritized banning the production and use of drugs, over ways to reduce or prevent harms associated with drugs.

There are many different drugs available through the illegal drug supply. Some drugs in this supply are illegally produced versions of pharmaceutical drugs, such as fentanyl, which was first approved in the United States in 1972 as an anesthetic.4 Strict rules about how pharmaceutical fentanyl and other pharmaceutical drugs are made, transported, stored and provided to patients help to ensure their safety. Similar rules do not exist for any substance sold in the illegal drug supply. Recognizing the role prohibition plays in creating and shaping risks related to illegal drugs is important to understanding and addressing harms driven by recent changes to the illegal drug supply. 

Changes in the illegal drug supply

Around 2013, fentanyl and other synthetic opioids started to be produced and sold in the illegal drug supply in North America.4 Fentanyl has replaced heroin as the dominant illegal opioid in most of Canada over the past decade and is now the primary driver of overdose deaths.1,5,6 Fentanyl is 20–40 times stronger than heroin.7 This extreme potency increases the risk of overdose, even in small amounts.1,5  Several factors have contributed to fentanyl’s rise in the illegal drug supply, including the following:4,8

  • Maximizing profits: Producers in the illegal market prioritize profit, not safety. Producing and transporting smaller volumes of more concentrated and powerful drugs like fentanyl is more profitable.9 Shifting from making heroin, which is made from organic materials, to fentanyl, which is much stronger and made with synthetic chemicals, significantly reduces costs and increases profits.
  • Filling market demand: Reduced opioid prescribing in North America left a gap in access to opioids. Illegal markets filled this gap by shifting toward producing and distributing fentanyl. 
  • Poor international control of precursor chemicals: In some countries, looser regulation of the chemicals used to make fentanyl allows these substances to be sold and transported to North America — often illegally. This makes it easier for illegal drug manufacturers to produce fentanyl domestically. 
  • Role of the Internet: The Internet facilitates knowledge sharing about newer and simpler fentanyl production methods. It has also increased the transportation of small packages. This has allowed fentanyl and its precursor chemicals to be shipped into and around North America undetected. 

More recent events, such as the COVID-19 pandemic and related border closures, led to an even more dangerous illegal drug supply.10,11 Since the COVID-19 pandemic, even stronger synthetic opioids (e.g., nitazenes, carfentanil) and sedatives (e.g., benzodiazepines, xylazine, medetomidine) have been detected or have become a lasting part of the drug supply in some regions.6,12–14 These drugs are most often added to fentanyl to further increase strength, reduce costs, increase profit or extend the effects of fentanyl.14,15 

Changes in the illegal drug supply can happen quickly — sometimes new drugs stay in the supply for a long time, and sometimes they leave as quickly as they appeared. It is important to note that these changes in North America’s illegal drug supply all started as decisions at the production and distribution level. These decisions are shaped by political and economic factors related to prohibition. Recent changes in the illegal drug supply have not occurred because of decisions by people who sell drugs at a retail level or by demand for these substances from people who use drugs.4,16,17 

What makes the illegal drug supply dangerous?

The lack of rules to guide the production and distribution of illegal drugs and recent changes to the drug supply have placed people who use drugs at increased risk.18 The factors that make Canada’s illegal drug supply dangerous are as follows:

  • the strength of drugs is unknown and unpredictable
  • the contents of drugs are unknown and unpredictable

Unknown and unpredictable strength

The strength of illegal drugs can vary widely and change unpredictably, significantly increasing the risk of overdose. This unpredictability is reflected in drug checking data and research findings. Data from drug checking services in different parts of the country show that the strength of illegal fentanyl can increase or decrease in huge swings.19,20 Sometimes the average strength of fentanyl can double or quadruple from one month to the next, with some individual samples being five times stronger than the month’s average.19,20 

These unpredictable changes in strength put people at risk of overdose. The body develops a tolerance for opioids slowly and it loses its tolerance quickly.21 This makes it difficult for the body to adapt to variations and spikes in the strength of opioids found in the illegal supply. Researchers have found that a higher monthly concentration of fentanyl in the drug supply has been linked to a higher death rate from illegal drugs in a given month.22

Unknown and unpredictable contents

The contents of illegal drugs are often unpredictable and unknown, which means that people can unexpectedly consume substances they did not intend to.23 This happens when 1) drugs are different from what people intended to use (e.g., thinking they are using heroin but the drug is fentanyl) or 2) drugs contain substances that people did not intend to consume (e.g., when benzodiazepines are added to fentanyl; when stimulants contain fentanyl).23 For example, recent studies have found that many people who use drugs across Canada were unaware that they had been consuming benzodiazepines.23,24 While the unexpected presence of fentanyl in stimulants is relatively rare25 and is probably due to accidents in packing or processing,26 it creates dangers for people who use stimulants. 

The consequences of unexpectedly being exposed to a substance can range from relatively harmless (e.g., the use of caffeine as a filler) to fatal (e.g., the presence of fentanyl in stimulants for people without a tolerance for opioids). Additionally, unexpected exposure can lead people to develop tolerance to substances (e.g., benzodiazepines) that they did not know they were using.15,27 This can lead to harms (e.g., unexpected and potentially fatal withdrawal), challenges with treatment initiation and retention (e.g., if withdrawal symptoms are not recognized and addressed) and complications related to overdose response protocols (e.g., people remaining unconscious after being given naloxone).15,27

Implications for service providers

Service providers across Canada have adapted significantly to respond to the dangers of the illegal drug supply. However, the increasingly unpredictable strength and contents of the illegal drug supply require continuous adaptation.

Changes in the illegal drug supply influence the dangers that people who use drugs face. To help mitigate these risks, service providers need to be informed about the nature of the drug supply so they can support service users, help reduce harms and adapt services and education. 

Supporting service users

  • Encourage safer use practices: Service providers can share harm reduction strategies to help people stay as safe as possible. These can include:
    • using at a supervised consumption or overdose prevention site, if possible
    • using with a trusted friend and taking turns to use
    • using a spotting service or calling a friend who can call for help if needed
    • using a very small amount to test how the person reacts to the drugs 
  • Promote drug checking services: Connect people to drug checking services, where possible. These services can help identify the contents and strength of the drugs, reducing potential harms.28 Drug checking services also monitor changes in the local drug supply and can engage with individuals who sell drugs to minimize risks for their clients.29
  • Prepare for unusual overdose symptoms: Be prepared to respond to unusual overdose symptoms such as prolonged sedation.15,27 Prioritize giving rescue breaths and providing naloxone to restore breathing. As the drug supply changes, updated approaches to overdose response might be needed. 
  • Facilitate access to treatment and safer alternatives: Support individuals who are interested to access treatment (e.g., opioid agonist treatment) and prescribed alternatives to illegal drugs, which can significantly reduce their risk of overdose.30,31 Service providers can also try to advocate for reduced barriers to access these services.

Key considerations

  • Regional drug supply awareness: The risk of overdose may vary by region because of differences in the local drug supply. These changes are not just the result of a “bad batch” of drugs but reflect the unregulated nature of the supply, where strength and contents can vary between doses, batches, over time and between communities. Staying up to date with the regional drug supply can involve talking to people who use drugs about what they’re experiencing and monitoring reports from drug checking services. 
  • Withdrawal risks: Be aware of substances found in your area’s illegal drugs and their associated withdrawal symptoms. People may develop tolerance to substances that are added to illegal drugs without realizing it, such as benzodiazepines. Unexpected withdrawal is of particular concern for people who are moving between settings (e.g., moving to a new community, being admitted to hospital, being incarcerated) and for people who are reducing or stopping their drug use (e.g., starting treatment). Medical care may be needed to address severe or life-threatening withdrawal symptoms.
  • Social and structural determinants of health: Factors such as lack of housing, unstable housing, poverty, racism and the ongoing impacts of colonialism increase the risk of overdose for certain individuals and communities.32 Recognizing the role that these factors play in individuals’ lives and supporting people to access services that can provide supports may help to reduce their risk of overdose and improve their overall well-being. 
  • Role of drug regulation: According to several expert groups, regulation of currently illegal drugs could provide ways to control the strength and contents of drugs, potentially reducing their harm.33–35 Regulation is a core part of public health approaches to all legal psychoactive substances, including alcohol, cannabis, tobacco and pharmaceutical drugs.36 It is standard in many other areas, including food safety (e.g., requiring “best before” dates) and road safety (e.g., drivers’ licences and speed limits).34

Additional resources

References

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  2. Harm Reduction International. Redirecting funds to harm reduction [cited 2024 Oct 15]. Available from: https://hri.global/topics/funding-for-harm-reduction/redirecting-funds/
  3. United Nations Office on Drugs and Crime (UNODC). Global synthetic drugs assessment 2020. Vienna: UNODC; 2020 [cited 2023 Aug 15]. https://www.unodc.org/unodc/en/scientists/2020-global-synthetic-drugs-assessment_Global.html
  4. Pardo B, Taylor J, Caulkins JP et al. The future of fentanyl and other synthetic opioids. Santa Monica (CA): RAND; 2019. Available from: https://www.rand.org/pubs/research_reports/RR3117.html
  5. Health Canada. Spotlight: the evolution of fentanyl in Canada over the past 11 years. 2023 Mar [cited 2023 Sep 11]. Available from: https://www.canada.ca/en/health-canada/services/publications/healthy-living/evolution-fentanyl-canada-11-years.html
  6. Kleinman RA. Fentanyl, carfentanil and other fentanyl analogues in Canada’s illicit opioid supply: a cross-sectional study. Drug and Alcohol Dependence Reports. 2024 Sep;12:100240. 
  7. Health Canada. Fentanyl. 2024 [cited 2024 Sep 14]. Available from: https://www.canada.ca/en/health-canada/services/substance-use/controlled-illegal-drugs/fentanyl.html
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  9. Beletsky L, Davis CS. Today’s fentanyl crisis: Prohibition’s Iron Law, revisited. International Journal of Drug Policy. 2017;46:156-9
  10. Health Canada, Public Health Agency of Canada, U.S. Department of Health and Human Services. Canada-U.S. joint white paper: substance use and harms during the covid-19 pandemic and approaches to federal surveillance and response. Ottawa (ON), Washington (DC): Health Canada, Public Health Agency of Canada, U.S. Department of Health and Human Services; 2022 [cited 2024 Nov 17]. Available from: https://www.canada.ca/en/public-health/services/publications/healthy-living/canada-us-white-paper-substance-use-harms-during-covid-19-pandemic-approaches-federal-surveillance-response.html
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  13. Canadian Centre on Substance Use and Addiction. CCENDU bulletin. Risks and harms associated with the nonmedical use of benzodiazepines in the unregulated drug supply in Canada. Ottawa (ON): Canadian Centre on Substance Use and Addiction; 2021 [cited 2023 Aug 24]. Available from: https://www.ccsa.ca/sites/default/files/2021-12/CCSA-CCENDU-Nonmedical-Use-Benzodiazepines-Unregulated-Drug-Supply-Bulletin-2021-en.pdf
  14. Gilbert ML, Maurice-Gelinas C, Rodrigues J et al. Spotlight: the emergence of xylazine in Canada. Ottawa (ON): Health Canada, Public Health Agency of Canada; 2023 [cited 2023 Aug 15]. Available from: https://www.canada.ca/content/dam/hc-sc/documents/services/publications/healthy-living/emergence-xylazine-canada/emergence-xylazine-canada-en.pdf
  15. Russell C, Law J, Bonn M et al. The increase in benzodiazepine-laced drugs and related risks in Canada: the urgent need for effective and sustainable solutions. International Journal of Drug Policy. 2023 Jan;111:103933. 
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  17. Montero F, Bourgois P, Friedman J. Potency-enhancing synthetics in the drug overdose epidemic: xylazine (“tranq”), fentanyl, methamphetamine, and the displacement of heroin in Philadelphia and Tijuana. Journal of Illicit Economies and Development. 2022;4(2):204-22.  
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  22. Kennedy MC, Dong H, Tobias S et al. Fentanyl concentration in drug checking samples and risk of overdose death in Vancouver, Canada. American Journal of Preventive Medicine. 2024;66(1):10-7.  
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  25. Canadian Centre on Substance Use and Addiction. CCENDU bulletin. An update on stimulant use and related harms in Canada and the United States. Ottawa (ON): Canadian Centre on Substance Use and Addiction; 2022 [cited 2024 Sep 14]. Available from: https://www.ccsa.ca/sites/default/files/2022-12/CCENDU%202022%20Stimulants%20Update.pdf
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  29. Larnder A, Burek P, Wallace B et al. Third party drug checking: accessing harm reduction services on the behalf of others. Harm Reduction Journal. 2021;18(1):1-4. 
  30. Slaunwhite A, Min JE, Palis H et al. Effect of risk mitigation guidance opioid and stimulant dispensations on mortality and acute care visits during dual public health emergencies: retrospective cohort study. BMJ. 2024 Jan 10;e076336. 
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Externally reviewed by: Amber Fritz, Samantha King & Doris Payer

Production of this article has been made possible through a financial contribution from Health Canada's Substance Use and Addictions Program. The views expressed herein do not necessarily represent the views of Health Canada.

About the author(s)

Magnus Nowell is CATIE’s knowledge specialist in harm reduction. Magnus has previously worked in harm reduction research, community organizing and housing. He has a master’s degree in health promotion.