Background: Opioid-related harms and opioid use disorder (OUD) are health priorities requiring urgent policy responses. There have been many calls for improved OUD care in primary care, as well as increasing involvement of primary care providers in countries like Canada and Australia, which have been experiencing high rates of opioid-related harms.

Methods: Using Starfield’s 4Cs conceptualization of primary care functions, we examined how and why primary care systems may be suited towards, or pose challenges to providing OUD care, and identified health system opportunities to address these challenges. We conducted 14 semi-structured interviews with 16 key informants with experience in opioid use policy in Canada and Australia.

Results: Primary care was identified to be an ideal setting for OUD care delivery due to its potential as the first point of contact in the health system; the opportunity to offer other health services to people with OUD; and the ability to coordinate care with other health providers (e.g. specialists, social workers) and thus also provide care continuity. However, challenges include a lack of resources and support for chronic disease management more broadly in primary care, and the prevailing model of OUD treatment, where addictions care is not seen as part of comprehensive primary care. Additionally, the highly regulated OUD policy landscape is also a barrier, manifesting as a ‘regulatory cascade’ in which restrictive oversight of OUD treatment passes from regulators to health providers to patients, normalizing the overly restrictive nature and inaccessibility of OUD care.

Conclusions: While primary care is an essential arena for providing OUD care, existing sociocultural, political, health professional, and health system factors have led to the current model of care that limits primary care involvement. Addressing this may involve structurally embedding OUD care into primary care and strengthening primary care in general.