Though it is a cannabis component, very high doses of CBD don’t appear to affect driving, a small Australian study reports.
Researchers from the University of Sydney found that even 1,500 mg, the highest daily medicinal dose of cannabidiol (CBD) tested, did not seem to affect study participants’ thinking skills or driving when tested in a simulated driving situation.
“Though CBD is generally considered ‘non-intoxicating,’ its effects on safety-sensitive tasks are still being established,” said lead author Danielle McCartney, a research associate at the university’s Lambert Initiative for Cannabinoid Therapeutics.
“Our study is the first to confirm that when consumed on its own, CBD is driver-safe,” she said in a university news release.
CBD does not appear to intoxicate people, researchers said. That’s unlike THC, another cannabis component that can induce sedation, a “high” and impairment.
Use of CBD is increasing in Western nations.
Around 55,000 requests to access medicinal CBD have been approved in Australia since 2016, according to a recent study. It is most commonly prescribed for pain, sleep disorders and anxiety.
For the new study, 17 participants did simulated driving tasks after consuming either a placebo or 15 mg, 300 mg or 1,500 mg of CBD in oil. These amounts represent often-used dosages.
Participants were asked to try to maintain a safe distance between themselves and a lead vehicle, and then “drive” along highways and rural roads. They completed the task between 45 and 75 minutes after taking their assigned treatment.
They did it again between 3-1/2 and four hours after dosing, which was meant to cover the range of blood plasma concentrations at different times. They repeated this under each of the four treatments — a placebo plus three different doses.
The researchers measured participants’ control of the simulated car, how much it weaved or drifted, as well as their thinking function, subjective experiences, and the CBD concentrations in their blood plasma.
The examinations found that no dose of CBD induced feelings of intoxication or appeared to impair either driving or thinking.
“We do, however, caution that this study looked at CBD in isolation only, and that drivers taking CBD with other medications should do so with care,” McCartney said.
The findings were published May 30 in the Journal of Psychopharmacology. A similar look at CBD and driving was published last year.
