Researchers at CU Anschutz studying cannabis users' ability to drive while high

Researchers with the School of Public Health at CU Anschutz have conducted a paid study to test cannabis users and determine levels of impairment.

For the last two years, more than 200 participants, ages ranging from 25-55 years old, have taken part in the study.

“With this study, we can understand how people change after cannabis use, how they drive differently, the reaction time, memory issues, blood or how the eyes change. The eyes in particular are one thing that police look for on the road,” said Dr. Ashley Brooks-Russell with the School of Public Health.“This is something we’ve been interested in for a while and we’re still seeing a lot of cannabis impaired crashes or people pulled over for cannabis impairment, so it’s still a big problem,” said Dr. Brooks-Russell. “Law enforcement doesn’t have a lot of tools to help detect who’s impaired from cannabis maybe versus some other substances. It’s not as straightforward as alcohol, so they really have a lot of challenges.”

During the study, participants are put into a room where they’re able to use high-concentrated cannabis, such as dabs, vape pens or edibles.

Once the cannabis sets into the person’s system, researchers take blood work, put participants through a series of tests on an iPad and then a driving simulator.

With the driving simulator, researchers are not checking how good a driver you are, but how bad a driver you may become while high on cannabis.

“We’re also interested in how those who use cannabis every single day might be different than people who do it occasionally. We know a lot of people use it for medical reasons and they can develop some tolerance and those individuals don’t seem to change as much as those who use occasionally."

Researchers noticed subtle driving changes to those who use recreational marijuana occasionally, such as weaving in and out of traffic, reaction time on the road, memory issues and changes in the eyes.

Visit the 9News website to learn more about the study.