Does Marijuana Affect Driving?
A federal study by the National Institute on Drug Abuse just concluded a detailed study to research the affects of marijuana on driving.
The research was conducted to learn about marijuana and its effects, and to compare it to using alcohol. The paper was primarily interested with these three parameters:
1. Weaving within the lane
2. The number of times the car left the lane
3. The speed of the weaving
The study recruited 18 different cannabis smokers with the participants being required to drive six different sessions on a driving simulator. Each session lasted 45 minutes a piece.
The results were both good and bad for marijuana supporters.
Marijuana did not effect the number of times the car left the lane or the speed of the weaving. However, alcohol did have a negative impact on both of those factors.
Marijuana did show an increase in weaving. In fact, drivers, with cannabis in their system showed increased weaving at the equivalent of those who drank and blew a .08 on a breathalyzer.
What made this study a little different, is that drivers THC levels were measured while they were driving. Most times, marijuana users are measured several hours after an arrest when their THC levels had time to reduce.
Not that there needed to be a study for this, but the study also found that a much more dramatic impact is felt when pot and alcohol are used together. (Can we say duh?)
The study also found that when alcohol and cannabis are combined, it takes longer for someone using both substances to feel drunk. THC actually delays the peak of alcohol impairment.