Acute Illness Associated With Cannabis Use, by Route of Exposure: An Observational Study

Ann Intern Med. 2019 Apr 16;170(8):531-537. doi: 10.7326/M18-2809. Epub 2019 Mar 26.


Background: Little is known about the relative harms of edible and inhalable cannabis products.

Objective: To describe and compare adult emergency department (ED) visits related to edible and inhaled cannabis exposure.

Design: Chart review of ED visits between 1 January 2012 and 31 December 2016.

Setting: A large urban academic hospital in Colorado.

Participants: Adults with ED visits with a cannabis-related International Classification of Diseases, Ninth or 10th Revision, Clinical Modification (ICD-9-CM or ICD-10-CM), code.

Measurements: Patient demographic characteristics, route of exposure, dose, symptoms, length of stay, disposition, discharge diagnoses, and attribution of visit to cannabis.

Results: There were 9973 visits with an ICD-9-CM or ICD-10-CM code for cannabis use. Of these, 2567 (25.7%) visits were at least partially attributable to cannabis, and 238 of those (9.3%) were related to edible cannabis. Visits attributable to inhaled cannabis were more likely to be for cannabinoid hyperemesis syndrome (18.0% vs. 8.4%), and visits attributable to edible cannabis were more likely to be due to acute psychiatric symptoms (18.0% vs. 10.9%), intoxication (48% vs. 28%), and cardiovascular symptoms (8.0% vs. 3.1%). Edible products accounted for 10.7% of cannabis-attributable visits between 2014 and 2016 but represented only 0.32% of total cannabis sales in Colorado (in kilograms of tetrahydrocannabinol) during that period.

Limitation: Retrospective study design, single academic center, self-reported exposure data, and limited availability of dose data.

Conclusion: Visits attributable to inhaled cannabis are more frequent than those attributable to edible cannabis, although the latter is associated with more acute psychiatric visits and more ED visits than expected.

Primary funding source: Colorado Department of Public Health and Environment.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Disease
  • Adult
  • Cannabis / adverse effects*
  • Cannabis / poisoning
  • Cardiovascular Diseases / chemically induced
  • Colorado
  • Emergency Service, Hospital
  • Female
  • Humans
  • Male
  • Marijuana Smoking / adverse effects*
  • Middle Aged
  • Plants, Edible / adverse effects*
  • Psychoses, Substance-Induced / etiology
  • Retrospective Studies
  • Vomiting / chemically induced