A recent clinical trial conducted by Montreal’s McGill University and funded by the Canadian Automobile Association found that younger drivers were riskier to be on the road up to 5 hours after having smoked or vaped cannabis.
In this randomized study, participants completed tests in a sober state and then at 1, 3 and 5 hour increments after inhalation of a 100-mg dose of cannabis. They then measured performance in driving-simulation type tests and obtained self-reported perceptions as well.
There were 45 participants who completed all 180 tests. The results were interesting to say the least. Cannabis had absolutely no effect on “simple driving related tasks,” but, before hopping behind the wheel, read on. The effect on complex tasks was significant, as was the participants’ own perceptions that they weren’t able to drive as safely.