Three noteworthy idiosyncrasies related to Canada's opioid-death crisis, and implications for public health-oriented interventions.

Canada has been experiencing a prolonged public health-crisis of high rates of overdose deaths caused by exceptionally potent/toxic, illicit opioid use. While many key features of this drug death epidemic are well-documented, several idiosyncratic aspects with relevance for public health-oriented interventions are not adequately recognised. These include: (i) the discrepant opioid patterns pan-Canada, with large majorities of opioid deaths caused by illicit fentanyl drugs in Western, but not Eastern regions where prescription-type opioid prevail; (ii) the environments of overdose deaths, where vast majorities occur in 'residential' or other shelter-type settings, presenting barriers for emergency interventions rather than health protection; and (iii) shifting drug use modes, where now majorities of overdose deaths are associated with drug 'inhalation' (instead of 'injection') in contexts of potent/toxic drug supply. We briefly describe these factors and related implications for intervention programming towards an improved response to the drug death-crisis.