It is beyond time for us to take drugged driving seriously. In a recent preliminary report, the National Highway Traffic Safety Administration (NHTSA) noted that, while drug use was already high among seriously or fatally injured accident victims before the pandemic, usage seems to have skyrocketed even more since.
The NHTSA found nearly 65% of drivers involved in serious or fatal accidents since the pandemic began tested positive for at least one active drug -- nearly 30% more than before the pandemic. More than 25% tested positive for two drugs, a nearly 44% increase. THC has also been more prevalent among drivers during the pandemic than alcohol (32.7% versus 28.3%), and opioid use among drivers almost doubled, from 7.5% to 13.9%.
Although alcohol is still a major contributing factor in many auto accidents, the alarming increase in fatalities is being attributed to the increasing availability of marijuana. The time is now for us step up our efforts to raise awareness and reduce drugged driving.
Marijuana, Not So Harmless
From my perspective, marijuana is an extremely problematic drug when it comes to drugged driving, and the numbers bear that out. There is a tacit assumption in our culture today – because it is legal or deemed medicinal in most states – that marijuana is safe. Previous posts on the Medicine, Science & Art blog have outlined that marijuana is not as safe as people think it is, especially for those under 25. The efficacy of marijuana and its properties for treatment of pain and disease still need significantly more research. We also do not know enough about how marijuana affects the ability to drive. How much is too much? How long after use is it dangerous to drive? We just don’t know.
Based on the research we do have on the physical effects of marijuana; we can logically deduce how marijuana affects driving ability. Marijuana causes drowsiness in many people. Visual perception may be impaired, as well as the ability to judge speed and distance – a sure recipe for disaster behind the wheel of a car. It may be difficult for drivers impaired by marijuana to keep a safe distance from the car in front of them. Because of drowsiness and lack of attention, impaired drivers may drift out of their lanes, or their reaction times may be too slow when steering or braking in emergencies. Overall, the anticipated side-effects of marijuana may compromise safe driving.
How Fast a High, and How Long?
The other reason I think marijuana is emerging as a dangerous factor in car accidents is because the effects of the drug when taken as an edible are different than when marijuana is smoked. This is not a minor issue because edibles are an increasingly legal form of recreational marijuana and are emerging as extremely popular and readily available – especially when more people are concerned with vaping making them more vulnerable to COVID-19.
When people smoke marijuana, the onset is very rapid. The inhaled THC passes through the lungs and into the blood stream and then to the brain very quickly. Within minutes of smoking marijuana, people start to feel the effect. It rapidly reaches a peak and then slowly wears off over several hours. To some extent, people can anticipate when the effects will wear off.
With edibles, however, it takes a significantly longer time for people to feel the effect. The blood levels may rise quickly, but the degree of impairment may not. People who use edible marijuana may not feel the maximum effect for an hour or two after consumption. People who are used to smoking marijuana may find they feel the major effects of edible marijuana just when they think they should be coming down. If they are driving when that happens, they could be severely impaired.
Not Easy to Test for Marijuana
Testing for marijuana impairment is not as easy as a field sobriety check for alcohol. With alcohol, an on-site breathalyzer test gives police a live and immediate picture of impairment. The only way to test for marijuana use is through blood tests.
To test someone for marijuana, that person must be taken to the police station or lab and have a blood sample drawn. That all takes time. Between the time a person was pulled over and the sample taken, the level of marijuana in the blood stream may have changed – making it an inaccurate and ineffective test. A new test using saliva is still in the experimental stages.
However, even if there were a simple way of doing an on-site test for marijuana use, medical research has yet to demonstrate a strong correlation between the serum levels of marijuana and the degree of impairment – meaning we don’t know how much marijuana or THC causes what level of driving impairment. This is especially true with edibles, where the blood level may be very low while the degree of impairment may be very high. Or, conversely, the blood level may be high while the degree of impairment is low. Researchers are looking for metabolites of THC that better correlate with the degree of impairment, but the science has a long way to go before it will be useful for law enforcement.
This lack of research is why 10 states have zero tolerance laws for driving under the influence of marijuana. It is also why a bill that passed the Pennsylvania House last year, that allows medicinal marijuana patients to drive, is highly disconcerting.
Prevention is Key
As marijuana continues to become more prevalent in our culture, rapid testing for marijuana impairment will be critical. It is equally critical that people are informed of the risks associated with marijuana use. We must bolster our education and prevention initiatives.
At this time, 17 states have now legalized recreational marijuana and more will follow. Therefore, we are likely to see an ongoing increase in the number of drivers who are under the influence of marijuana.
A recent study conducted by Liberty Mutual Insurance and SADD (Students Against Destructive Decisions), reported that 33 percent of all teens surveyed perceive it to be legal to drive under the influence of marijuana in states where it’s been legalized for recreational use. Notably, 27 percent of parents surveyed believe it to be legal as well. The survey also found that only 76 percent of parents and 68 percent of teens feel that driving under the influence of marijuana is dangerous.
As a society, we appropriately make a big deal about driving under the influence of alcohol, given the potentially deadly consequences. Marijuana may be more subtle than alcohol in the outward signs of impairment, but it clearly is the cause behind a growing number of fatal automobile accidents.
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