Cannabis Effects on Driving-related Skills of Young Drivers

Summary

Motor vehicle collisions are the leading cause of death for young people. The investigators have recently found that driving after using cannabis is more common among young Canadian drivers than driving after drinking. While this observation raises concerns, the effects of cannabis on driving-related skills in this age group are not well understood. As well, evidence suggests that residual effects of cannabis on driving-related skills may be observed up to 24 hours later. These residual effects may have important implications for the effects of cannabis use on collision risk, but little evidence on them in available. This study will examine the effects of a single dose of cannabis (marijuana) on driving-related skills immediately following consumption, 24 hours later, and 48 hours later. To date, the residual effect at 48 hours has not been examined. A total of 142 subjects aged 19 to 25 years old will be randomly assigned to smoke either a placebo or active cannabis cigarette (12.5% THC potency). Following an eligibility screening and practice session, participants will attend 3 testing days; drug-administration, 24-hour follow-up and 48-hour follow-up. The effects of cannabis/placebo on performance of driving-related skills using a high-fidelity driving simulator will be assessed on each testing day. The effects of cannabis on mood, cognition, memory and complex reaction time will also be assessed. Identifying factors that affect the collision risks experienced by young drivers is a public health priority. While many young people believe that cannabis does not impair driving, some recent studies suggest that these may be very dangerous beliefs. This study will provide important information on how cannabis may affect the driving skills of young drivers, to inform efforts to understand and address cannabis-related collision in this age group.

Conditions

• Psychomotor Impairment

Interventions

DRUG

delta-9-tetrahydrocannabinol

A single cannabis cigarette (potency 12.5% THC) will be given to participants to smoke over a 10 minute period, ad lib. If the cigarette is not smoked in its entirety, the remainder will be weighed to estimate dose.

DRUG

Placebo

A single placebo cannabis cigarette (0% THC) will be given to participants to smoke over a 10 minute period, ad lib. If the cigarette is not smoked in its entirety, the remainder will be weighed to estimate dose (as this is a double-blind study).

Sponsors & Collaborators

• Canadian Institutes of Health Research (CIHR)

  collaborator OTHER_GOV

• Health Canada

  collaborator OTHER_GOV

• Centre for Addiction and Mental Health

  lead OTHER

Principal Investigators

• Robert Mann, Ph.D. · Centre for Addiction and Mental Health

• Bernard Le Foll, M.D., Ph.D. · Centre for Addiction and Mental Health

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

19 Years

Max Age

25 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2012-07-31

Primary Completion

2016-08-31

Completion

2016-09-30

Countries

• Canada

Study Locations