Opioids produce feelings of euphoria and general well-being and have been used throughout history to treat pain and a variety of different ailments.2 In the 21st century, opioids are available as regulated, pharmaceutical medications and in unregulated non-medical forms (e.g., heroin), which have become increasingly adulterated with highly potent opioids, such as fentanyl, over time.3 Use of opioids falls on a spectrum, from non-harmful (e.g., temporary use for pain management) to stable long-term use to uncontrolled use leading to serious health and social concerns (e.g., opioid use disorder). Movement along this spectrum can occur in either direction over the course of time and a variety of complex individual and societal factors can influence whether an individual’s use produces harmful consequences.

Opioid use disorder (OUD) is best conceptualized as a chronic relapsing condition; though associated with elevated rates of morbidity and mortality, individuals with OUD have the potential for sustained long-term remission with appropriate treatment and support. Opioid use disorder is characterized by craving, uncontrolled use, and continued use despite significant consequences.4 Most individuals also experience withdrawal symptoms when opioids are discontinued. Canadian OUD prevalence estimates are lacking. However, national survey data found that approximately 3.7 million (12.7%) Canadians used an opioid pain medication in 2018, with approximately 10% of those (351,000 Canadians) reporting problematic use, defined as using in larger amounts or more frequently than prescribed, using to get high or for reasons other than pain management, or tampering with the medication before using it.5 Data from the British Columbia OUD Cohort  indicates that there was a 19.2% increase in diagnosed opioid use disorder between September 2018 and September 2020. It should be noted, however, that the factors underlying this increase are not well understood; for example, improvements in screening and documentation practices may have contributed to an increase in the number of individuals identified, but the extent of this contribution is unclear. 

Opioid poisoning continues to be the leading cause of unnatural death in British Columbia, surpassing homicides, suicides, and motor vehicle collisions combined.6 At least 32,632 Canadians died from an opioid overdose between January 2016 and June 2022.7 Although every part of Canada has been impacted by the drug poisoning crisis, BC has seen both the highest number and the highest rate (41.3/100,000 in January–September 2021) of toxic drug deaths.8,9 Since 2016, when a public health emergency was declared in BC, to 2022, at least 9,760 British Columbians have died from opioid toxicity.6 Within BC, Northern Health Authority had the highest rate (58/100,000), while Fraser Health Authority had the highest number of toxic drug deaths (236 deaths) in 2022.9,10 At the population level, BC’s life expectancy at birth, which had increased by almost 3 years from 2000 to 2013 (80.27 to 83.02 years of age), declined by 0.38 years from 2014 to 2016 as a direct consequence of drug toxicity deaths.11 In 2020 alone, an estimated almost 70,000 potential years of life were lost due to unregulated drug toxicity deaths in BC, with the average age at death being 43 years old.12 The alarming rise in toxic drug deaths has been accompanied by a host of other drug-related harms affecting communities across the province, including brain injuries from non-fatal drug poisonings, which have contributed to morbidity and mortality, as well as significant costs to the health care system.13 

The primary driver of this crisis is the growing toxicity and unpredictability of illegally-manufactured and -distributed drugs, such as fentanyl and other highly potent synthetic opioids. While unregulated opioids are often intentionally purchased, their potency and composition are largely unknown and may differ with each purchase. Additionally, non-opioid drugs are increasingly adulterated or contaminated with fentanyl or other synthetic opioids.14 Higher fentanyl concentrations and an increase in unexpected, dangerous combinations of drugs (e.g., benzodiazepines and fentanyl) have been observed across multiple drug surveillance data sources across the province.  

Fentanyl was detected in approximately 86% of overdose deaths in 2021 and 82% of toxic drug deaths in 2022, which represent substantial increases from 2012 when 3% of deaths involved fentanyl.7 Carfentanil, a highly potent synthetic opioid used as anesthesia in large animals,15,16 was detected in 192 drug toxicity deaths in 2021, and 126 suspected drug toxicity deaths in 2022. 7  An investigation of whether drug-related deaths between 2015 and 2017 involved prescribed or non-prescribed medications revealed that 83% of deaths involved non-prescribed opioids, with fentanyl or its analogues being the most prevalent type of opioid detected (found in 79% of deaths related to non-prescribed opioids).17 Contamination of street drugs is ongoing and progressive, with new agents such as benzodiazepine analogues, and xylazine found in substances sold as opioids.18 

In response to the ongoing and evolving drug toxicity crisis in which the drug supply continues to intensify in toxicity, clinicians, and researchers have pioneered innovative treatment and research protocols with the intention of improving patients’ experiences of initiation and stabilization on opioid agonist treatment (OAT). Over the five years that have passed since the 2017 publication of A Guideline for the Clinical Management of Opioid Use Disorder, evidence, best practices, and clinical expertise have also evolved. The new 2023 guideline will reflect this evolution and ensure health care providers have access to updated recommendations and clinical guidance aligned to the best evidence on the full continuum of care for opioid use disorder.