Cannabis Edibles and Simulated Driving

Dose-dependent Effects of Cannabis Edibles on Simulated Driving Performance

The goal of this human laboratory experiment is to determine the acute and residual effects of a range of doses of orally administered cannabis edibles on driving simulator performance in people who use cannabis recreationally. Four conditions will be tested: placebo, low dose, medium dose and high dose. Driving performance will be tested objectively using a driving simulator during a number of pre-programmed driving scenarios. The investigators will test the hypothesis that driving performance on a high-fidelity driving simulator will decrease with increasing doses of cannabis. Secondary objectives will:

• Determine the acute and residual (24 hour) cognitive, behavioural, and physiological effects of a range of doses of orally administered cannabis edibles on subjective effects, cognitive tests, verbal memory, and mood.
• Examine how the concentration of THC in blood and oral fluids correlates with driving simulator performance, as well as cognitive, behavioural, and physiological measures. Cannabinoid levels in blood, urine and oral fluids will be measured at baseline and over a 5 hour period following drug exposure. The investigators will examine the relationship between cannabinoid levels and performance measures in this time frame.
• Explore potential biomarkers of acute exposure to cannabis edibles by analyzing the following: circulating cell-free mtDNA (ccf-mtDNA), endocannabinoids, and metabolic biomarkers.

Study Overview

• Status: Completed
• Conditions: Cannabis; Driving Under the Influence
• Intervention / Treatment: Drug: Cannabis - Placebo Dose (0 mg); Drug: Cannabis - Low Dose (2 mg); Drug: Cannabis - Medium Dose (10 mg); Drug: Cannabis - High Dose (20 mg)

• Study Type: Interventional
• Enrollment (Actual): 52
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5S 2S1
      • Center for Addiction and Mental Health

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Provides written and informed consent
• Stated the willingness to comply with all study procedures
• Recreational use of oral, vaped, smoked or edible cannabis (at least one day/week) and cannabis edibles (at least one day/month) confirmed by self-report and urine screening (i.e., positive THC result in point-of-care screening or Clinical Laboratory assay)
• Males and females aged 19 to 45 years
• Has held a class G license (or equivalent from another jurisdiction) for at least 12 months
• Willing to abstain from using cannabis for 72 hours prior to each practice or test session
• Willing to abstain from alcohol for 48 hours prior to each practice or test session, and to abstain from all other drugs not medically required for the duration of the study (beginning 48 hours prior to the practice session)
• Lives within a radius that costs less than about $60 per taxi ride
• Able to consume the quantity of candies and drive the driving simulator as determined by a practice session
• A negative urine pregnancy test for those with childbearing potential
• Use of appropriate contraception for those with childbearing potential

Exclusion Criteria:

• Diagnosis of severe medical or psychiatric condition (e.g., diagnosis of a severe mood or anxiety disorder, based on self-report
• Meets criteria for current or lifetime alcohol or other substance use disorder (DSM-5), except tobacco use disorder and caffeine use disorder
• Regular user of medication that may affect cognitive functioning and/or driver performance (e.g. ADHD medication, benzodiazepines, stimulants, opioids)
• Regular user of illicit substances
• Personal or family history of schizophrenia or other psychotic disorder
• Pregnant, looking to become pregnant, or breastfeeding
• Concomitant therapy with sedative-hypnotics or other psychoactive drugs
• Severe laboratory abnormalities that could create safety issues based on the judgement of the Principal Investigator
• Cardiovascular or cerebrovascular disease
• Severe renal or liver disease
• Participation in another clinical or non-therapeutic study in the past month

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Placebo Cannabis Edibles (0 mg THC); Participants consume a placebo dose of cannabis edibles (0 mg THC).	Drug: Cannabis - Placebo Dose (0 mg); Participants will consume placebo cannabis edibles.
Experimental: Low Dose Cannabis Edibles (2 mg THC); Participants consume a low dose of cannabis edibles (2 mg THC).	Drug: Cannabis - Low Dose (2 mg); Participants will consume a low dose (2 mg) of cannabis edibles.
Experimental: Medium Dose Cannabis Edibles (10 mg); Participants consume a medium dose of cannabis edibles (10 mg THC).	Drug: Cannabis - Medium Dose (10 mg); Participants will consume a medium dose (10 mg) of cannabis edibles.
Experimental: High Dose Cannabis Edibles (20 mg); Participants consume a high dose of cannabis edibles (20 mg THC).	Drug: Cannabis - High Dose (20 mg); Participants will consume a high dose (20 mg) of cannabis edibles.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Standard Deviation of Lateral Position (SDLP)	The driving simulator will objectively record SDLP during a number of pre-programmed driving scenarios.	Before cannabis exposure; 2 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated on the test for residual effects, approximately 24 hours after dosing.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Speed (MS)	The driving simulator will objectively record MS during a number of pre-programmed driving scenarios.	Before cannabis exposure; 2 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated on the test for residual effects, approximately 24 hours after dosing.
Reaction Time (RT)	The driving simulator will objectively record RT during a number of pre-programmed driving scenarios.	Before cannabis exposure; 2 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated on the test for residual effects, approximately 24 hours after dosing.
Standard Deviation of Speed (SDS)	The driving simulator will objectively record SDS during a number of pre-programmed driving scenarios.	Before cannabis exposure; 2 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated on the test for residual effects, approximately 24 hours after dosing.
Blood concentrations of Δ9-tetrahydrocannabinol (THC), 11-hydroxy-Δ9-tetrahydrocannabinol (OH-THC), and 11-Nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH)	Used to assess THC and metabolite concentrations (ng/mL) in blood.	Before cannabis exposure; 2 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated on the test for residual effects, approximately 24 hours after dosing.
Oral fluid concentrations of Δ9-tetrahydrocannabinol (THC), 11-hydroxy-Δ9-tetrahydrocannabinol (OH-THC), and 11-Nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) and point-of-care detection of cannabinoids	Used to assess THC and metabolite concentrations (ng/mL) in oral fluid.	Before cannabis exposure; 2 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated on the test for residual effects, approximately 24 hours after dosing.
Heart Rate	Heart rate (bpm) will be measured.	Before cannabis exposure; 0, 30, 60, 90 minutes and 2, 3, 4 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated approximately 24 hours after dosing.
Blood Pressure	Systolic and diastolic blood pressure (mmHg) will be measured.	Before cannabis exposure; 0, 30, 60, 90 minutes and 2, 3, 4 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated approximately 24 hours after dosing.
Temperature	Temperature (degrees Celsius) will be measured.	Before cannabis exposure; 0, 30, 60, 90 minutes and 2, 3, 4 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated approximately 24 hours after dosing.
Visual Analog Scale (VAS)	Used to assess subjective effects of cannabis on a sliding scale of 0 (not at all) to 100 (maximum effect).	Before cannabis exposure; 0, 30, 60, 90 minutes and 2, 3, 4 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated approximately 24 hours after dosing.
Addiction Research Centre Inventory (ARCI)	Used to assess subjective effects of cannabis.	Before cannabis exposure; 2 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated on the test for residual effects, approximately 24 hours after dosing.
Profile of Mood States (POMS)	Used to assess subjective effects of cannabis.	Before cannabis exposure; 2 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated on the test for residual effects, approximately 24 hours after dosing.
Verbal Free Recall Task	Used to assess the impact of cannabis on verbal learning and memory.	Before cannabis exposure; 2 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated on the test for residual effects, approximately 24 hours after dosing.
Blood Concentrations of mtDNA	Used to assess concentrations of mtDNA.	Before cannabis exposure; 2 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated on the test for residual effects, approximately 24 hours after dosing.
Blood Concentrations Endocannabinoids	Used to assess concentrations of endocannabinoids.	Before cannabis exposure; 2 and 5 hours after cannabis exposure (repeated each session for 4 sessions). Also repeated on the test for residual effects, approximately 24 hours after dosing.

Collaborators and Investigators

• Sponsor: Centre for Addiction and Mental Health
• Investigators: Principal Investigator: Bernard Le Foll, MD, PhD, Centre for Addiction and Mental Health

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2024
• Primary Completion (Actual): April 4, 2025
• Study Completion (Actual): April 4, 2025

Study Registration Dates

• First Submitted: September 6, 2024
• First Submitted That Met QC Criteria: September 12, 2024
• First Posted (Actual): September 19, 2024

Study Record Updates

• Last Update Posted (Actual): August 3, 2025
• Last Update Submitted That Met QC Criteria: July 30, 2025
• Last Verified: February 1, 2025

More Information

Terms related to this study

• Keywords: Cognition; THC; Subjective Effects; Cannabinoids; Driving Simulator; Cannabis Edibles
• Additional Relevant MeSH Terms: Mental Disorders; Substance-Related Disorders; Chemically-Induced Disorders; Marijuana Abuse
• Other Study ID Numbers: 074-2020

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No