Acute cannabis intoxication in the emergency department: the effect of legalization

On October 17, 2018, the Cannabis Act decriminalized the recreational use of cannabis in Canada. This study seeks to determine how legalization of cannabis has impacted emergency department (ED) visits for acute cannabis intoxication.

We conducted a retrospective chart review at an academic ED in Hamilton, Ontario. We assessed all visits with a cannabis-related ICD-10 discharge code 6 months before and after legalization (October 17, 2018) to determine cases of acute cannabis intoxication. The primary outcome was the rate of ED visits. Secondary outcomes included number of visits distributed by age, length of stay, co-ingestions, and clinical course in the emergency department (investigations and treatment).

There was no difference in the overall rate of ED visits following legalization (2.44 vs. 2.94 visits/1000, p = 0.27). However, we noted a 56% increase in visits among adults aged 18-29 (p = 0.03). Following legalization, a larger portion of patients required observation without interventions (25% vs 48%, p < 0.05). Bloodwork and imaging studies decreased (53% vs. 12%, p < 0.05; 29% vs. 2%, p < 0.05); however, treatment with benzodiazepines increased (24% vs. 51%, p < 0.05).

Legalization was not associated with a change in the rate of cannabis-related ED visits in our study. More research is needed regarding changing methods of cannabis ingestion and trends among specific age groups.