The University of Sydney research team studied the effects of cannabidiol (CBD) on driving, and they found that the highest daily medicinal dose of CBD (1,500mg) had no negative impact on driving or cognitive ability. This is the first study to confirm CBD is driver-safe, and the findings were published in the Journal of Psychopharmacology.
As drivers become more aware about safe CBD use and driving, professional transportation associations in various countries are also preparing for policy changes that have implications for safe driving practices. The United States Department of Transportation issued a notice in 2020 in response to increased hemp product use and truckers’ questions about acceptable use. The DOT explained that professional drivers should avoid any hemp derived products until federal policy changes and there is further clarification how these changes impact CDL (Commercial Driver License) drivers. DOT also indicated that although cannabinoids such as Delta 8 and Delta 10 are legal in some states, using such products places professional truckers at risk of failing a drug test. Some cannabinoids share the same metabolites as tetrahydrocannabinol (THC), and a drug screening test may indicate a false positive for THC. Legally prescribed opiates and other potentially sedating or psychoactive medication medications prescription meds do not violate policy if the person has a legitimate prescription.
The University of Sydney team observed 17 participants complete driving performance tasks after consuming either a placebo or 15, 300 or 1500 mg of CBD. First, participants were instructed to maintain a safe distance between themselves and a lead vehicle roughly between 45-75 minutes after their first assigned CBD dose. The route was along highways and rural roads. They completed the task again between 3.5 and four hours after. These intervals covered the range of plasma concentrations at different times. Participants repeated each of the four different treatments (placebo plus three different doses).
Measurements of participants’ control of the simulated car was tested by how much it weaved or drifted. Cognitive function, subjective experiences, and CBD concentrations in their plasma were also measured. No participants reported CBD induced feelings of intoxication or impairment of driving or cognitive performance, and researchers did not observe any effects on their coordination or thought processing.
Although CBD on its own did not reduce driver safety, drivers who use CBD and other medications should consult their physician to discuss interactions that could decrease alertness and reflexes.
Source: Journal of Psychopharmacology
