Responding to an evolving crisis: Meeting the needs of a growing population who smoke their unregulated substances.

Jurisdictions across Canada are experiencing high and increasing numbers of drug toxicity (overdose) deaths. To effectively respond to this crisis, a recognition and adaptation to shifting substance use patterns is needed. People may use one or more modes of consumption (e.g. injection, inhalation, snorting, oral, rectal), with different modes of consumption presenting different opportunities and challenges for public health education and intervention. In recent years, inhalation has increasingly been identified as a major mode of consumption for unregulated substances. We discuss the implications and what is needed to respond. We argue that (1) more research and evidence focused specifically on services for people who smoke unregulated substances is needed; (2) inhalation services that have an acceptable evidence base, even if incomplete, should be implemented and rigorously monitored, to be responsive to an ongoing public health crisis; and (3) there is a need to be mindful of the implications of delays in services for people who inhale drugs. We acknowledge the efforts of public health decision-makers to learn from the context of public health emergencies when it comes to upholding evidence-based practice standards. In this context, it will be important for decision-makers to remain agile in responding to complex public health issues that are characterized by ongoing and acute harms, political tensions, and a growing yet incomplete body of evidence, such as the evolving drug toxicity crisis.