The study examines how strict the driving laws are in Australia and what impact they have on patients who use medical cannabis. It also looks at their attitude towards driving under influence.
Driving a vehicle with detectable levels of THC is prohibited in most Australian states, regardless of the patient’s level of impairment or whether they have a cannabis medical prescription. Tasmania is currently the only Australian state to offer a medical defence.
The Australian laws are being challenged right now by various organizations and politicians. They effectively act as a ban on driving, as THC is detectable up to a week after consumption, long after impairment has occurred.
Researchers from several Australian universities carried out a cross sectional online survey of Australians who used cannabis to treat a medical problem between December 20,22 and April 20,23. The focus was on the driving issue. In addition to demographics and clinical data, the self-reported driving while under influence of cannabis was also assessed, along with driving related behaviours and opinions about impairment.
73% reported using medical cannabis prescribed to them and 28,3% driving under the Influence of Cannabis.
The likelihood of driving under the influence was significantly higher when a person used medical cannabis more frequently, was male, smoked or illicit cannabis and believed that it did not affect driving. According to 69.1%, those who reported DUIC did not believe they were impaired. However, as stated above impairment or lack of it does not change the way driving laws are applied.
Twenty-seven percent of patients who use medical marijuana orally, thirty seven percent of those who smoke, and sixteen per cent of those using vaporisers said they felt safe driving within an hour.
In 2021, researchers at Australia’s Lambert Initiative for Cannabinoid Therapeutics at the University of Sydney indicated a ‘window of impairment’ of between three and 10 hours based on moderate to high doses of THC – but that impairment was not a straightforward situation.
One fifth of survey participants in this latest study had tested positive for drugs at roadside in the past 12 months. The roadside testing deterred many people from driving when they used medical cannabis. Over half of those who were deterred either stopped or changed the kind of medical cannabis that was being consumed.
Further findings
- 80.0 % of drivers said that they could accurately assess their driving skills after using medical cannabis.
- 81% of respondents said they tend to drive more cautiously.
- 58% of drivers said they tend to keep a bigger gap between themselves and the vehicle in front.
- The majority of drivers (55.8%) felt that they had more control over their vehicle.
- 75.0% strongly disagreed, or disagreed, that they react slower in sudden situations.
- 83% of respondents disagreed that it is harder to stay focused.
- 88.0% of respondents disagree that it is harder to drive straight.
- 95.7 % of respondents disagreed that they took more risks.
The study authors commented on the findings and said that while it is clear roadside testing deters drivers, it can also be a barrier for patients to access treatment.
As cannabis policy continues to change and patient access increases, it is important to take into account the therapeutic benefits of marijuana. To better understand the effects of medical cannabis, including driving and cognitive impairments, more research is required.
Study has been published Transportation Research Part F – Traffic Psychology and Behaviour.