This retrospective cohort study aimed to determine the effect of opioid and stimulant Risk Mitigation Guidance (RMG) dispensations on mortality and acute care visits during the dual public health emergencies of overdose and COVID-19. The study found that RMG opioid dispensations were associated with reduced overdose related and all cause mortality among a sample of people with opioid use disorder, and demonstrates that pharmaceutical alternatives to the illegal drug supply are promising interventions to reduce mortality in people with opioid use disorder.