A critical study has shown how cannabis affects driving ability. The study reveals that Cannabidiol (CBD), a cannabis component now widely used for medical purposes, does not affect driving. In contrast, moderate amounts of the main intoxicating component tetrahydrocannabinol (THC) produce mild driving impairment, lasting for up to four hours.
What is Cannabidiol?
Cannabidiol is a popular natural medication used by many for treating common illnesses. It is better known as CBD and is among the 100s of chemical compounds known as cannabinoids. We can find them in the cannabis or marijuana plant, Cannabis sativa.
As of 2019, clinical research on CBD combined with studies related to anxiety, cognition, movement disorders, and pain. Still, there is insufficient high-quality evidence that cannabidiol is useful for these conditions.
People take cannabidiol in several ways: by inhalation of cannabis smoke or vapor, as an aerosol sprays into the cheek, and by mouth. It also comes as CBD oil, containing only CBD as the active ingredient (excluding tetrahydrocannabinol [THC] or terpenes).
Is cannabidiol CBD legal in the US?
As of March 2020, cannabidiol extracted from marijuana remains a Schedule I Controlled Substance, and the United States does not approve other CBD formulations as a prescription drug or dietary supplement or allow their interstate commerce.
In 2018, the Food and Drug Administration in the United States approved cannabidiol drug Epidiolex to treat two epilepsy disorders.
Side effects of cannabidiol
Research indicates that cannabidiol may reduce THC’s adverse effects, particularly those causing intoxication and sedation, but only at high doses. Safety studies of cannabidiol have shown that it is well-tolerated but may cause tiredness, diarrhea, or appetite changes as common adverse effects. Epidiolex documentation lists sleepiness, insomnia n and poor quality sleep, decreased appetite, diarrhea, and fatigue.
CBD sans THC does not affect driving ability
The study was led by the Lambert Initiative for Cannabinoid Therapeutics at the University of Sydney and administered at Maastricht University in the Netherlands. The report got published today in the prestigious Journal of the American Medical Association.
According to lead author Dr. Thomas Arkell: “for the first time, these findings indicate that CBD, when given without THC, does not affect a subject’s ability to drive. That is excellent news for those using or considering treatment using CBD-based products.”
Using cannabis for medical treatment
There has been phenomenal growth in medical treatment using cannabis-related products in Australia and overseas. It includes an increase in the use of CBD-containing products for conditions such as epilepsy, anxiety, chronic pain, and addictions. Numerous currently available products also comprise a mixture of THC and CBD.
The research included people inhaling vaporized cannabis containing different THC and CBD mixes, then going for a 100-kilometer drive under controlled circumstances on public highways both 40 minutes and four hours later. Cannabis comprising mainly CBD did not affect driving, while cannabis carrying THC, or a THC/CBD mixture, led to mild impairment when measured 40 minutes later but not after four hours.
Results giving promising insights
“With cannabis laws changing worldwide, jurisdictions are grappling with the issue of cannabis-impaired driving. These results present much-needed insights into the magnitude and duration of impairment induced by different types of cannabis. They can help guide road-safety policy not just in Australia but around the globe,” said Dr. Arkell.
According to Dr. Arkell, “Road safety is of paramount importance. These results should provide for evidence-based laws and regulation for people receiving medical cannabis.”
Professor Iain McGregor, who is currently serving as the Academic Director of the Lambert Initiative, said: “We were overwhelmed to have the opportunity to work in collaboration with Professor Jan Ramaekers and his team on this study. To comprehend the impact of cannabis on driving with such precision in a real-world context is very crucial.
“The results should are optimistic for the people using CBD-only products that they are most likely safe to drive while helping patients using THC-dominant products to understand the duration of the impairment.”
The method adopted for the study
The study included giving 26 healthy participators four distinct types of cannabis in a random fashion to vaporize on four different occasions. Every participant’s driving performance was evaluated on a 100-kilometer stretch of a public highway in real-world conditions in a dual control car with a driving instructor present.
The researchers conducted these tests at Maastricht University in the Netherlands using a well-established scientific analysis that estimates the standard deviation of vehicle position (SDLP), an index of lane weaving, swerving, and overcorrecting.
SDLP increases when the person is under the influence of alcohol and drugs such as Valium and Stilnox.
Participants vaporized cannabis comprising primarily THC, primarily CBD, THC, CBD in combination, or placebo cannabis (no active components). The quantity of THC vaporized by participants was sufficient to induce intense feelings of intoxication.
Participants finished two one-hour, on-road highway driving tests starting at 40 minutes and four hours following inhaling vaporized cannabis to test how the distinct types of cannabis affect driving.
According to Professor McGregor: “Rapidly changing attitudes towards medical and non-medical use of cannabis is leading to driving under the effect of cannabis and is appearing as an essential and slightly questionable public health issue.
“While some previous studies have shown the effects of cannabis on driving, most of them have concentrated on smoked cannabis comprising only THC (not CBD) and have not explicitly quantified the duration of the impairment.
“This is one of a kind study to demonstrate the lack of CBD effects on driving and also provides a clear indication of the duration of THC impairment.”