More Folks Drive High When Pot Made Legal

These deficits result in sluggish response time, lack of focus and weaving down the highway, Brubacher stated.

“We know that the danger of crashing is increased in ingesting drivers than in drivers who use hashish,” he stated. “Some earlier researchers instructed that hashish legalization might enhance site visitors security if drivers used hashish as a substitute of alcohol. Unfortunately, we discovered no proof of a lower within the share of injured drivers who examined constructive for alcohol.”

Volkow famous the results of marijuana on driving means are appreciable.

“Numerous research have demonstrated that marijuana considerably impairs most of the expertise wanted for protected driving, together with judgment, motor coordination and response time. Studies carried out in a laboratory setting have additionally discovered a direct relationship between the focus of THC within the blood and impaired driving means,” she stated.

“However, this analysis have to be interpreted with warning, as it may be extraordinarily troublesome to ascertain the causality for any given automotive crash. This is as a result of – not like for alcohol – there isn’t any roadside check to measure drug ranges within the physique,” Volkow defined. “This signifies that exams used to detect THC ranges in drivers are sometimes carried out hours after the crash. Further, marijuana may be detected in bodily fluids for days or perhaps weeks after final use, and drivers usually mix it with alcohol, making it troublesome to know the way important a task hashish alone might have performed in a crash.”

For the examine, Brubacher and his colleagues analyzed ranges of THC in blood samples from greater than 4,300 injured drivers who have been handled at British Columbia trauma facilities between 2013 and 2020.

Before pot was legalized, about 4% of drivers had blood ranges of THC above the Canadian authorized driving restrict of two ng/mL. That share rose to just about 9% after legalization, the researchers discovered.

The proportion of drivers with increased concentrations of THC additionally rose, from 1% earlier than legalization to 4% after.

The largest improve was seen amongst drivers over 50. No important modifications in drivers testing constructive for alcohol, both alone or together with THC, was seen, the researchers famous.

Delayed driving suggested

The share of these driving each drunk and excessive was about 2% earlier than legalization and three% after, the examine authors discovered.

Blood ranges of THC often peak at round 100 ng/mL inside quarter-hour of smoking pot. The ranges then drop quickly, to lower than 2 ng/mL inside 4 hours of smoking. After ingesting edible THC, the degrees drop to a equally low focus after eight hours, Brubacher stated.

Based on these knowledge, he advises folks to not drive for 4 hours after smoking pot and eight hours after ingesting it. Brubacher additionally cautioned that the mixture of alcohol and pot may be particularly lethal behind the wheel.

“Even although these numbers are regarding, and I feel there may be some cause for concern, it is not the sky is falling,” he stated. “It’s not as critical an issue as it could be if we noticed a doubling within the variety of drivers who have been utilizing alcohol, as a result of the danger is much less with THC than with alcohol.”

The similar improve in marijuana use whereas driving has been seen within the United States in states the place it has been legalized.

According to Paul Armentano, deputy director of NORML, a gaggle that advocates for the reform of marijuana legal guidelines within the United States, “Similar elevated prevalence knowledge has additionally been reported in some U.S. states, like Washington, with out a statistically important uptick in site visitors fatalities.”

While testing for THC may be troublesome, Armentano cautioned that folks mustn’t drive whereas feeling “excessive.”

“NORML has an extended historical past of calling for focused public training campaigns concerning the affect of acute hashish consumption on driving efficiency, and we consider that such campaigns must be half and parcel with any adult-use legalization legislation,” Armentano stated. “We even have an extended historical past of calling for offering legislation enforcement with further and extra correct instruments and strategies to each determine and discourage DUI [driving under the influence] hashish conduct.”

The report was revealed Jan. 13 within the New England Journal of Medicine.

More info

For extra on marijuana and driving, head to the U.S. National Institute on Drug Abuse.

SOURCES: Jeffrey Brubacher, MD, affiliate professor, division of emergency drugs, University of British Columbia, Vancouver, Canada; Paul Armentano, deputy director, NORML, Washington, D.C.; New England Journal of Medicine, Jan. 13, 2022