Driving After Using High-Potency Marijuana & Extracts

In the U.S., motor vehicle accidents are the leading cause of death among adolescents and young adults aged 16-25 years.

Marijuana legalization in the United States has resulted from the ballot box and Madison Avenue marketing strategies but not through rigorous clinical trials to determine the safety and efficacy.

Consequently, the dramatic increase in drugged driving fatalities and injuries is directly related to the user’s beliefs in the potential for harm. This well-constructed survey of marijuana users confirms what other studies have proven. A significant relationship exists between the perception of harm and marijuana driving impairment and mortality. This association is stronger among people who use high-potency cannabis (THC) extracts. The research team examined the perception of harm and the experiences of driving under the influence of potent THC extracts.

Driving After Using Marijuana

The study asked participants about driving after using marijuana. In Study 1, phone interviews (n = 19) were conducted with people who use high THC content cannabis extracts. In Study 2, people who use extracts (n = 174) were recruited to participate in a nationwide survey via an existing online panel. Responses to marijuana and driving-related questions were qualitatively coded for themes (e.g., riskiness, engagement in behavior) that were developed by the research team.

Ask the ExpertThe overarching themes identified in Study 1 suggested a belief that driving risk following marijuana use is dependent on the individual personal response and/or tolerance, plus the amount and type of marijuana consumed. This theme was corroborated by Study 2 participants. Those who perceived no or minimal risk from driving following marijuana use were more likely to report engagement in driving after using high potency THC.

The authors suggest that more research is needed to understand how marijuana, especially in its concentrated form, impacts driving ability to the end point of developing appropriate and scientifically sound regulations. They assert that such research could subsequently improve and more widely disseminate prevention messages on marijuana use and driving risks. I, along with others, am not convinced that pure educational information regarding the risks is something that would prevent initiation, considering that the age of onset is 12 or 13 in the U.S. Parental education aimed at increased parental involvement is a more likely avenue to prevent or delay initiation.

Why Does This Matter?

Marijuana users who reject assertions that cannabis use causes enough impairment to operate a motor vehicle unsafely and therefore drive while intoxicated place the public at increased risk. The prevalence of weekend nighttime driving under the influence of marijuana (based on biochemical assays) among drivers aged ≥16 years has increased by 48%, up from 8.6% in 2007 to 12.6% in 2013-2014. Use of marijuana alone and in combination with alcohol has been shown to impair reaction time, spatial awareness, executive functioning and perceptions of risk. This level of impairment has been observed empirically 24 hours after using cannabis. To put a finer point on this, cannabis users equate “feeling good” (being high) with “being good” (actual performance and behavior). This is a dangerous public health problem.