What is it about?

This study looked at the impact of Ontario's recreational cannabis policy on emergency department (ED) visits related to cannabis. The policy included the legalization of cannabis flowers and herbs (Phase 1) in October 2018, followed by the deregulation of cannabis retailers and sales of edibles (Phase 2) about one year later. The study analyzed data from adults who had continuous health insurance coverage between 2015-2021, and examined the impact of the policy on different age, gender, and geographic groups. The study found that both Northern and Southern Ontario showed similar patterns of changes in cannabis-related ED visits after the policy changes, with Phase 1 leading to significant increases in adults aged 25-64, particularly women aged 45-64, and Phase 2 leading to immediate increases in adults aged 18-44 of both genders, with larger increases in women than men. Though both regions showed similar cannabis-related ED-visits, Northern Ontario was found to be higher. The study suggests that while current preventive efforts focus on reducing cannabis-related harms in younger people, adults aged 25-64, particularly women, have been significantly impacted by the policy changes. The study recommends further research on gender-specific cannabis dosage and targeted interventions for adult women. Also, the higher rates of ED visits in Northern Ontario should be addressed.

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Why is it important?

Given the implementation of recreational cannabis policies around the world, it is important to evaluate the impact of legalization on healthcare systems in order to inform policy changes.


Findings from this paper are particularly strong since we analyzed data from all eligible recipients of Ontario's universal healthcare system (which contains >95% of the population of the province).

Antony Chum
York University

Read the Original

This page is a summary of: Associations between recreational cannabis legalization and cannabis-related emergency department visits by age, gender, and geographic status in Ontario, Canada: An interrupted time series study, PLoS ONE, October 2022, PLOS,
DOI: 10.1371/journal.pone.0268718.
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