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Cannabis poisoning in young children increased nine times after legalization


Largest increase seen after legalization of commercial cannabis edibles

Ontario saw nine times more emergency department (ED) visits per month for cannabis poisonings in young children after Canada legalized recreational cannabis, according to a study published in JAMA Network Open. While single hospitals have reported on child cannabis poisonings before, this is the first study to look at an entire region.

“We saw more frequent and severe ED visits due to cannabis poisoning in children under 10 following the legalization of cannabis, and the legalization of edible cannabis products appears to be a key factor,” said lead author Dr. Daniel Myran, a family physician, public health and preventive medicine specialist, and postdoctoral fellow at The Ottawa Hospital and the University of Ottawa Department of Family Medicine.

The research team looked at all ED visits in Ontario during three periods; pre-legalization, after flower-based cannabis products and oils were legalized in October 2018, and after commercial cannabis edibles (e.g. gummies and chocolates) and other products were legalized and became available for sale in late January 2020.

During the entire study period (January 2016 to March 2021), there were 522 ED visits for cannabis poisoning in children under 10. The average age of these children was 3 years, 9 months.

While there were no deaths, 171 (32.7%) visits required hospitalization and 19 visits (3.6%) required ICU admission. ED visits for cannabis poisonings increased the most after commercial edibles were legalized, and more of these visits required hospitalization compared to the other two periods (39% compared to 25%).

Study results:

Pre-legalization (January 2016-Sept 2018)

  • Total ED visits: 81
  • Average number of ED visits per month: 2.5
  • Percentage of ED visits that were hospitalized: 25%

Legalization of cannabis flower, seed and oil (October 2018-January 2020)

  • Total ED visits: 124
  • Average number of ED visits per month: 7.8
  • Increase in average monthly ED visits compared to pre-legalization: 3 times
  • Percentage of ED visits that were hospitalized: 24%

Legalization of edibles and other products (Feb 2020-March 2021)

  • Total ED visits: 317
  • Average number of ED visits per month: 22.6
  • Increase in average monthly ED visits compared to pre-legalization: 9 times
  • Percentage of ED visits that were hospitalized: 39%

The researchers noted that cannabis legalization in Canada overlapped with the COVID-19 pandemic. They found that while ED visits for pediatric poisonings of any kind decreased in Ontario during the pandemic, visits for cannabis poisonings increased. After commercial edibles became available, nearly 10% of all ED visits for poisonings in children in Ontario were related to cannabis.

“Canada’s approach to legalization was intended to prevent increases in child cannabis poisonings through policies limiting the strength of cannabis edibles, requiring child resistant packaging and education for parents and caregivers.” said Dr. Myran. “Unfortunately, the rates we saw in our study suggests the approach has not met that goal.”

“As more places around the world consider legalizing recreational cannabis, we need to learn how to better protect children from cannabis poisoning. This could include stricter rules about packaging and appearance, more education for parents and caregivers, or not permitting products that are particularly appealing to children.

If your child has accidentally consumed cannabis, contact the Ontario Poison Control Centre at 1-800-268-9017. Cannabis poisoning in babies and children is a medical emergency. Call 9-1-1 if your child is ill and/or has difficulty breathing. Caregivers can prevent poisonings by keeping cannabis products in a locked container away from other food and drinks, and out of children’s reach. Learn more about the risks of cannabis and how to prevent unintentional poisoning.

Researchers at ICES, Bruyère Research Institute, the Canadian Centre on Substance Use and Addiction and SickKids also contributed to this study.

Funding: This study was funded by ICES and the Canadian Institutes of Health Research

Data sources: ICES, Canadian Institute for Health Information, Ontario Ministry of Health

Full reference: Unintentional pediatric cannabis exposures following legalization of recreational cannabis in Canada. Daniel Myran, Nathan Cantor, Yaron Finkelstein, Michael Pugliese, Astrid Guttmann, Rebecca Jesseman, Peter Tanuseputro. JAMA Network Open. Jan 7, 2022.

About the Ottawa Hospital
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About the University of Ottawa
The University of Ottawa is home to over 50,000 students, faculty and staff, who live, work and study in both French and English. Our campus is a crossroads of cultures and ideas, where bold minds come together to inspire game-changing ideas. We are one of Canada’s top 10 research universities—our professors and researchers explore new approaches to today’s challenges. One of a handful of Canadian universities ranked among the top 200 in the world, we attract exceptional thinkers and welcome diverse perspectives from across the globe. www.uottawa.ca

About the Bruyère Research Institute
The Bruyère Research Institute supports investigators who contribute to a better, more responsive healthcare system that delivers the best care to patients, residents and families. The Institute is a proud partner of Bruyère Continuing Care, the University of Ottawa and others and provides solutions to improve the health and healthcare of aging and vulnerable Canadians. The Institute is home to the Centre for Individualized Health, an innovative data science hub that creates evidence to improve health decision-making.

ICES is an independent, non-profit research institute that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy. In October 2018, the institute formerly known as the Institute for Clinical Evaluative Sciences formally adopted the initialism ICES as its official name. For the latest ICES news, follow us on Twitter: @ICESOntario

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Amelia Buchanan
Senior Communication Specialist
Ottawa Hospital Research Institute
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