Drivers who get behind the wheel within three hours of smoking pot are nearly twice as likely to cause a car accident as those who aren’t under the influence of drugs or alcohol, a new study has found.
Researchers from Dalhousie University in Nova Scotia reviewed nine studies involving 49,411 people to determine whether the consumption of marijuana increases the risk of a motor vehicle collision.
They found the risk of being involved in a crash nearly doubled for drivers who got high before hitting the road. Marijuana use impairs drivers’ reaction time and affects judgment, they said.
Researchers, who published their findings in the online edition of the British Medical Journal, noted previous results have also found that there is also a substantially higher chance of collision if the driver is aged 35 or younger.
All motor vehicle collisions involved in the study took place on a public road and involved one or more moving vehicles such as cars, vans, sports utility vehicles, trucks, buses and motorcycles.