June 25, 2015

Study Finds Driving Impairment from Marijuana Use Similar to That of Alcohol Use

While some young people believe marijuana use has little-to-no effect on driving ability, a new study found that marijuana use impairs driving similar to alcohol use. The study, funded by the National Institute on Drug Abuse (NIDA), the Office on National Drug Control Policy (ONDCP), and the National Highway Traffic Safety Administration (NHTSA), was released this week and published in the journal Drug and Alcohol Dependence.

Using a driving simulator, researchers found that marijuana use impairs one measure of driving performance. People driving with blood concentrations of 13.1 µg/L THC – the main psychoactive ingredient in marijuana – showed increased weaving within the lane, similar to those with 0.08 breath alcohol, the threshold for impaired driving in many states.

The study found that drinking alcohol and smoking marijuana had an additive effect, so that drivers using both substances weaved within lanes even if their blood THC and alcohol concentrations were below the impairment thresholds for each substance alone.

CADCA’s Mid-Year Training Institute will offer several courses for health advocates on the topic. One course, “Marijuana’s Impact on Highway Safety: Drugged Driving,” from 8:30 a.m. to Noon Aug. 5, will focus on the research behind and prevention messages to address the public and highway safety. Participants will learn about the latest science behind driving under the influence of drugs with an emphasis on the effects of marijuana-induced impairment and issues surrounding measuring levels of the drug to prove impairment. Additionally, these presenters will go deeper into the science about marijuana’s impact on public safety and the associated costs to communities. CADCA’s Mid-Year Training Institute offers half-day and two-day courses for new, established and veteran drug prevention professionals in eight subject areas. Learn more about the training tracks, key speakers and other details about CADCA’s Mid-Year Training Institute. Register today.
 

SEE ALSO:
 

CADCA TV Show: “Drugged Driving: The Hidden Dangers”
 

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