Determine the extent and duration of driving and acute cognitive impairment induced by Δ9-tetrahydrocannabinol (Δ9-THC)
How long should you wait after consuming cannabis before driving? The answer is not straightforward, according to a study and meta-analysis of the effects of cannabis on driving and driving cognition.
While the study confirms that THC interferes with driving, there is no simple formula for how long to wait before driving, as the effects depend on many factors, including whether a person or a regular cannabis user.
The key, according to the authors, is to wait at least seven hours after inhaling cannabis - and longer after ingesting it - before driving or engaging in other safety-sensitive tasks.
As more states legalize the use of cannabis for recreational and medical purposes, lawmakers want to know how THC poisoning affects road safety so that they can regulate what constitutes safe behavior. Unfortunately, the duration of THC impairment has not been well established and, unlike in the case of alcohol, there is no precise measure of intoxication because there is no clear relationship between blood THC levels and impairment.
By analyzing 80 scientific articles, the study Current research has shown that THC has significant adverse effects on lateral control and reaction time while driving, as well as mental skills essential for safe driving, including sustained attention and fine motor skills.
Interestingly, maintaining distance from the previous vehicle, speed, and speed variability were not affected by THC.
The extent of impairment was less for regular users and depended on the amount of cannabis consumed and the time elapsed since consumption, making it impossible to enforce hard and fast rules. The study suggests that impairment may last longer - perhaps up to 10 hours - after oral ingestion of 20 mg of THC.
A previous study of National Academies of Sciences, Engineering, and Medicine found that driving under the influence of cannabis increased the risk of traffic accidents.
Another study of the Lambert Initiative for Cannabinoid Therapeutics from the University of Sydney analyzed the effects of cannabis and its components on the driving skills of users, finding that cannabidiol (CBD) does not cause impaired driving abilities and that tetrahydrocannabinol (THC) has only mild effects on driving for four hours.
The Departmental Highway Safety Board in conjunction with Michigan State Police investigated the rpre-existing research on the relationship between the effects of THC on driving and has conducted its own tests on road fluids.
As cannabis for medical use becomes more readily available, it is imperative that the risks associated with driving are clarified by extensive research.
These recommendations are in agreement with others, in particular the guidelines on low-dose cannabis use. risk approved by Health Canada, which recommend waiting at least six hours, and the recommendation of the College of Family Physicians of Canada to wait at least eight hours after inhalation or ingestion if the user experiences euphoria.