Does Unit-Dose Packaging Influence Understanding of Serving Size Information for Cannabis Edibles?

J Stud Alcohol Drugs. 2020 Mar;81(2):173-179.


Objective: Edible cannabis products have increased in popularity, particularly in jurisdictions that have legalized nonmedical cannabis. Rates of adverse events from cannabis edibles have also increased, in part because of difficulties identifying and titrating tetrahydrocannabinol (THC) levels. The current study tested whether packaging cannabis in separate units enhances consumer understanding of serving sizes.

Method: An experimental task was conducted as part of the 2018 International Cannabis Policy Study online survey. Participants were recruited from the Nielsen Global Insights Consumer Panel. A total of 26,894 participants (61.5% female) ages 16-65 years from Canada and the United States were randomly assigned to view a cannabis brownie packaged according to one of three conditions: (a) multiserving edible ("control condition"), (b) single-serving edible, and (c) single-serving edible packaged separately ("unit-dose packaging"). Participants were asked to identify a standard serving based on information on the product label. Logistic regression was used to test the influence of packaging condition on the likelihood of a correct response, adjusting for key covariates.

Results: Compared with the multiserving edible control (50.6%), participants were significantly more likely to correctly identify the serving size in the single-serving edible condition (55.3%; adjusted odds ratio = 1.22, CI [1.15, 1.29], p < .001) and the unit-dose packaging condition (54.3%; adjusted odds ratio = 1.17, CI [1.10, 1.24], p < .001).

Conclusions: Packaging in which each product unit contained one dose of THC enhanced consumers' ability to identify how much of a product constitutes a standard serving or dose. Packaging products as individual doses eliminates the need for mental math and could reduce the risk of accidental overconsumption of cannabis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Canada / epidemiology
  • Cannabis / adverse effects
  • Comprehension*
  • Dronabinol / administration & dosage*
  • Dronabinol / adverse effects
  • Dronabinol / standards
  • Female
  • Hallucinogens / adverse effects
  • Hallucinogens / standards
  • Humans
  • Male
  • Marijuana Use / epidemiology
  • Marijuana Use / psychology*
  • Marijuana Use / trends
  • Middle Aged
  • Product Packaging / standards*
  • Serving Size / adverse effects
  • Serving Size / psychology*
  • Serving Size / standards*
  • Surveys and Questionnaires
  • United States / epidemiology
  • Young Adult


  • Hallucinogens
  • Dronabinol

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