Citation

Hartley S, Simon N, Cardozo B, Larabi IA, Alvarez JC. Front. Public Health 2023; 11: e1234765.

Copyright

(Copyright © 2023, Frontiers Editorial Office)

DOI

10.3389/fpubh.2023.1234765

PMID

38074719

PMCID

PMC10703156

Abstract

AIMS: To study the effect of inhaled cannabis on self-assessed predicted driving ability and its relation to reaction times and driving ability on a driving simulator. PARTICIPANTS AND METHODS: 30 healthy male volunteers aged 18-34: 15 chronic (1-2 joints /day) and 15 occasional (1-2 joints/week) consumers. Self-assessed driving confidence (visual analog scale), vigilance (Karolinska), reaction time (mean reciprocal reaction time mRRT, psychomotor vigilance test), driving ability (standard deviation of lane position SDLP on a York driving simulator) and blood concentrations of delta-9-tétrahydrocannabinol (THC) were measured before and repeatedly after controlled inhalation of placebo, 10 mg or 30 mg of THC mixed with tobacco in a cigarette.

RESULTS: Cannabis consumption (at 10 and 30 mg) led to a marked decrease in driving confidence over the first 2 h which remained below baseline at 8 h. Driving confidence was related to THC dose and to THC concentrations in the effective compartment with a low concentration of 0.11 ng/ml for the EC50 and a rapid onset of action (T1/2 37 min). Driving ability and reaction times were reduced by cannabis consumption. Driving confidence was shown to be related to driving ability and reaction times in both chronic and occasional consumers.

CONCLUSIONS: Cannabis consumption leads to a rapid reduction in driving confidence which is related to reduced ability on a driving simulator.

CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02061020.

Keywords: Cannabis impaired driving

Language: en

Keywords

accident; cannabis; reaction time; driving simulator; driving