Cannabis study finds CBD doesn't impact ability to drive, but THC does

A new study published in a notable medical journal has found that cannabidiol (CBD), one of the multiple compounds found in cannabis, does not impair one's ability to drive. That's good news for the growing number of people who utilize CBD products in a medicinal way, but there is a point of caution. The same study reports that THC, the psychoactive compound, does impair driving — though the effect doesn't last long.

Cannabidiol, which is sold under the acronym CBD, isn't psychoactive unlike its THC sibling, which causes the stereotypical 'high' associated with marijuana. The compound may have anti-inflammatory properties and has been found to help with certain medical conditions, including reports of easing pain and reducing seizures.

Controversy exists over driving in relation to using medicinal cannabis. It's clear that THC impairs driving ability, but CBD is a different matter. This new study from the University of Sydney and Maastricht University is the first to find that CBD doesn't impair driving if it is consumed in the absence of THC.

To test whether the substance impaired driving, the researchers had participants inhale cannabis vapor containing different mixes of CBD and THC. Afterward, the participants drove on public highways (under controlled conditions) 40 minutes later; they repeated the drive four hours later, as well.

Cannabis that contained mostly CBD wasn't found to impair driving whereas cannabis containing a mix of both compounds or mainly THC was found to cause 'mild' impairment during the first drive. However, the same impairment (after moderate consumption) wasn't found during the second drive four hours later. The researchers note that this study can help communities develop guidance and regulations on driving while under the influence of cannabis.