Edible and flower cannabis users showed similar intoxication and memory impairment despite different blood THC levels

In a naturalistic study of 84 legal-market cannabis users, flower users had higher blood THC levels but similar THC metabolite levels, subjective intoxication, and verbal memory impairment compared to edible users.

Bidwell, L Cinnamon et al.·Psychopharmacology·2022·Moderate EvidenceObservational
RTHC-03712ObservationalModerate Evidence2022RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Observational
Evidence
Moderate Evidence
Sample
N=84

What This Study Found

Flower users consumed an average of 51.25 mg THC vs. 15.97 mg for edible users. Plasma THC was significantly higher after flower use, but THC metabolite levels, subjective intoxication, and verbal memory impairment were comparable between groups. Self-reported THC consumed correlated strongly with plasma THC for edible but not flower users.

Key Numbers

84 participants; flower users consumed 51.25 mg THC on average vs. 15.97 mg for edible users. Similar levels of intoxication and verbal memory impairment despite the dose difference.

How They Did This

Naturalistic study of 84 participants (55 flower, 29 edible users, mean age 32, 44% female) who used cannabis at least once weekly. Participants underwent blood draws, heart rate measurement, subjective drug effects assessment, and cognitive testing before and after ad libitum use of legal market products in a mobile laboratory.

Why This Research Matters

This is one of the first studies to directly compare the pharmacology and effects of legal market edible and flower cannabis under naturalistic conditions, providing data more relevant to real-world use than laboratory studies with standardized products.

The Bigger Picture

The finding that edible and flower users reach similar levels of impairment despite different doses and blood levels challenges simplistic dose-response assumptions and highlights the complexity of cannabis pharmacology across delivery methods.

What This Study Doesn't Tell Us

Non-randomized design (participants self-selected their product type). Unequal group sizes. Ad libitum dosing means results reflect typical use patterns rather than controlled comparisons. Single-session assessment.

Questions This Raises

  • ?Why do edible users achieve similar impairment with lower doses?
  • ?Does tolerance develop differently for each route?
  • ?Could edible dosing guidelines be based on these naturalistic findings?

Trust & Context

Key Stat:
Similar impairment despite 3x dose difference between flower and edible users
Evidence Grade:
Novel naturalistic design with legal market products, but non-randomized and moderate sample size.
Study Age:
Published in 2022.
Original Title:
A naturalistic study of orally administered vs. inhaled legal market cannabis: cannabinoids exposure, intoxication, and impairment.
Published In:
Psychopharmacology, 239(2), 385-397 (2022)
Database ID:
RTHC-03712

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

Watches what happens naturally without intervening.

What do these levels mean? →

Frequently Asked Questions

Do edibles and flower produce different levels of impairment?

In this study, despite flower users consuming about three times more THC (51 mg vs. 16 mg), both groups showed similar levels of subjective intoxication and verbal memory impairment after ad libitum use.

Why did edible users consume less THC but feel equally intoxicated?

Edible users may titrate their dose more effectively to reach their desired effect, or the metabolic pathway for oral THC (which produces the potent metabolite 11-OH-THC) may produce comparable effects at lower doses.

Read More on RethinkTHC

Cite This Study

RTHC-03712·https://rethinkthc.com/research/RTHC-03712

APA

Bidwell, L Cinnamon; Karoly, Hollis C; Torres, Marco Ortiz; Master, Ashley; Bryan, Angela D; Hutchison, Kent E. (2022). A naturalistic study of orally administered vs. inhaled legal market cannabis: cannabinoids exposure, intoxication, and impairment.. Psychopharmacology, 239(2), 385-397. https://doi.org/10.1007/s00213-021-06007-2

MLA

Bidwell, L Cinnamon, et al. "A naturalistic study of orally administered vs. inhaled legal market cannabis: cannabinoids exposure, intoxication, and impairment.." Psychopharmacology, 2022. https://doi.org/10.1007/s00213-021-06007-2

RethinkTHC

RethinkTHC Research Database. "A naturalistic study of orally administered vs. inhaled lega..." RTHC-03712. Retrieved from https://rethinkthc.com/research/bidwell-2022-a-naturalistic-study-of

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.