Mixing Cannabis with Ethanol
Scientifically, the consensus is unanimous: consuming alcohol impairs driving ability and increases the risk of crashing. The United States of America has seen decades of public awareness campaigns educating drivers about the dangers and consequences of drinking and driving. What we haven’t seen as frequently are warnings about consuming THC—the chemical in cannabis responsible for the high cannabis users feel—and driving. This may be partly because cannabis use has been illegal for decades, and the assumption may have been that drivers already know they shouldn’t be consuming any illegal substance in the first place, much less driving while impaired. Another possible reason may be that testing for THC concentrations is more difficult than testing for blood alcohol concentrations (BAC), and the results less accurate. Whatever the reasons for the specificity of anti-drinking and driving campaigns, cannabis is now firmly a priority of traffic safety authorities as states look to legalizing medicinal and recreational use of the plant.
Rightly so, because the science on the matter indicates that automatic functions like reaction time and perception of speed—functions that make the difference between a crash and responding to an obstruction in the road in time to avoid a crash—are impaired by low doses of THC.
As the social stigma and criminal consequences of using cannabis evaporate, use of the already popular drug will likely be more commonplace. Add another substance to the list of recreational drugs Americans may use legally and it seems plausible that the result will be more cases of people using the drugs concurrently. Sometimes, those people will also choose to drive while intoxicated. In the case of mixing alcohol and THC, that may be very bad news for traffic safety.
Limited studies have found that consuming alcohol increases absorption of THC into the bloodstream. When drivers were given low doses of THC and alcohol together, they performed worse than they did when given the same doses of each drug separately. In one study, drivers were given enough alcohol to have a BAC of 0.04 percent, along with low THC doses of 100 and 200 ㎍/㎏. Driving performance when dosed with both alcohol and THC at 100 and 200 ㎍/㎏ was comparative to driving with a 0.09 and 0.14 BAC, respectively. Comprehensive studies of drunk driving have found that driving with a BAC between 0.05 and 0.09 percent increases the likelihood of a fatal crash 11 times over driving while sober, and driving with a BAC between 0.1 and 0.14 makes a fatal crash 48 times more likely.
People who might feel that they are being reasonably responsible by consuming only a little bit of cannabis and a little bit of alcohol suddenly become dangerous. Perhaps worse is that a driver can pass a breathalyzer test, but end up driving with an impairment equivalent to a BAC well above the legal limit.
Pro tip: State governments will be throwing money at the first company to produce an accurate roadside test for blood THC concentration.
Ultimately, when it comes to using cannabis and alcohol before driving: don’t do it.
Accidents are the leading cause of death for Americans under the age of thirty. Cars arefast- moving, heavy machines, and no person should be impaired while driving. We shouldn’t drink any amount of alcohol before driving; we shouldn’t consume any amount of THC before driving; and, especially, we shouldn’t mix alcohol and cannabis before driving.