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Government Studying How Marijuana Affects Drivers


Government researchers are studying the effect of marijuana on drivers, USA Today reports. The findings will help regulators decide on guidelines for drugged driving.

The study is looking at the effect of marijuana alone, as well as the combination of marijuana and alcohol. The data has been collected and is now being analyzed. The study is similar to research that was conducted to determine the legal limit for drivers’ blood alcohol levels.

Study participants did not drive on real roads, the article notes. They used a simulator that mimics real driving conditions. Before using the simulator, participants consumed specific combinations of marijuana and alcohol, or a placebo. They used a vaporizer to consume their marijuana because the study took place at the University of Iowa, which is smoke-free.

The marijuana in the study was provided by a federal growing facility at the University of Mississippi. The study included 19 participants who gave blood and saliva tests so researchers could verify their intoxication levels. The investigators hope to have preliminary data available by October.

“In this country, there’s a huge controversy over whether there should be zero tolerance or there should be some level that’s acceptable. It’s a terribly difficult problem,” said Marilyn Huestis, Chief of Chemistry and Drug Metabolism at the Intramural Research Program at the National Institute on Drug Abuse. “We will be looking at what are the kinds of functions that are affected, and whether they are significantly different … whether alcohol is on board or not.”

4 Responses to this article

  1. Eric Martin / August 5, 2014 at 1:59 pm

    I agree with Stephanie. They need to test people who smoke BHO and Kief, and people who consume edibles. They also need to assess CBD levels in drivers too. A person could have a high THC level in their blood that may be theoretically mitigated by CBD which is believed to be an antagonist. Real natural marijuana runs in fairly close 1:1 ratio of THC to CBD, this why so many people report that smoking real marijuana doesn’t get you high (Nebraska no-high, etc.). There needs to be a way of testing both THC and CBD in the blood in this research study.

  2. Lisa / August 4, 2014 at 3:55 pm

    I really hope some guidelines are established. I am concerned about my own teenager driving after he has used marijuana. I have nothing to base my concerns on, and teens like to argue that they are “fine” and not impaired. Yet they smoke to feel high or buzzed??

  3. Carl Olsen / August 1, 2014 at 6:42 am

    I hope they are honest enough to test marijuana and alcohol separately, as well as in combination. Combining alcohol with anything will result in impairment.

  4. Stephenie Roberts / July 31, 2014 at 2:05 pm

    In the past the Mississippi cannabis did not have as high a THC content as what is currently being cultivated across the country. Has this changed?

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