Marijuana Use By Drivers Linked With Increased Risk of Motor Vehicle Crashes

Drivers who test positive for marijuana or who drive within three hours of using marijuana are more than twice as likely to be involved in motor vehicle crashes compared with those who don’t use the drug, according to a new review of studies.

Science Daily reports researchers at Columbia University in New York combined the results of nine studies, and found the greater the amount of marijuana compounds in a person’s urine, the greater the risk of a car crash. The study also found more frequent self-reported marijuana use was associated with a greater risk of a motor vehicle accident.

The study found 28 percent of drivers who died in an accident, and more than 11 percent of drivers in general, tested positive for non-alcohol drugs. Marijuana was the most commonly detected substance.

Eight of the nine studies found drivers who use marijuana are significantly more likely than people who don’t use marijuana to be involved in motor vehicle accidents. The results appear in the journal Epidemiologic Reviews.

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    Dr. Winston De La Haye

    October 12, 2011 at 12:12 PM

    I am not aware of any of the studies mentioned being done “in Jamicia with some poor guy chopping trees, not opperating a vehicle”!

    I treat patients in Jamaica on a daily basis with Marijuana Misuse. 90% of them operate a vehicle!

    Very important findings.

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    October 10, 2011 at 1:52 PM

    Just like someone who take a prescription drug any so-called marijuana patients should not have a right to drive. As for the studies you mention i’m sure they were done in Jamicia with some poor guy chopping trees, not opperating a vehicle.

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    October 7, 2011 at 4:12 PM

    There have also been studies that show regular users are relatively unaffected as far as motor skills and decision making. Also marijuana takes a long time to leave the system and can be stored up which might make testing difficult. While it is not ok to drive impaired i worry about legislation regarding this issue because it could render medical patients unable to function as normal members of society.

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