With the increasing use of Cannabidiol (CBD), a major cannabinoid found in the Cannabis sativa plant, for treating various conditions, it's crucial to understand its effects on cognitive tasks like driving. A recent study titled "Effects of cannabidiol on simulated driving and cognitive performance: A dose-ranging randomised controlled trial" delves into this topic.
Introducing the Study
This study is a human trial conducted by Danielle McCartney, Anastasia S Suraev, Peter T Doohan, Christopher Irwin, Richard C Kevin, Ronald R Grunstein, Camilla M Hoyos, and Iain S McGregor from various institutions, including the Lambert Initiative for Cannabinoid Therapeutics and The University of Sydney.
Key Findings
- Acute, oral CBD treatment does not appear to induce feelings of intoxication.
- CBD is unlikely to impair cognitive function or driving performance.
- Residual CBD was found to persist in plasma for prolonged periods of time, e.g., >4 weeks at 1500 mg.
Delving into the Methodology
The study involved 17 healthy adults who completed four treatment sessions. These sessions included the oral administration of a placebo, or 15, 300, or 1500 mg of CBD in a randomised, double-blind, crossover design. Simulated driving performance was assessed at two intervals post-treatment, and cognitive function, subjective experiences, and plasma CBD concentrations were also measured.
The primary outcome was the standard deviation of lateral position (SDLP), a well-established measure of vehicular control. Non-inferiority analyses were used to test the hypothesis that CBD would not increase SDLP by more than a margin equivalent to a 0.05% blood alcohol concentration.
Potential Implications
The findings of this study could have significant implications for the use of CBD, especially for those who need to perform safety-sensitive tasks like driving. The results suggest that CBD, even in high doses, does not impair cognitive function or driving performance.
Limitations of the Study
One limitation of the study was the unexpected finding that CBD persisted in plasma for prolonged periods of time. This could potentially influence the results, although the study argues that the low, residual levels of CBD are unlikely to have had a major effect on performance. Future studies should measure plasma CBD concentrations and consider that CBD doses ⩾300 mg may not ‘washout’ within 7 days.
Concluding Thoughts
While CBD is generally considered 'non-intoxicating', its effects on safety-sensitive tasks are still under scrutiny. This study suggests that acute, oral CBD treatment does not induce feelings of intoxication and is unlikely to impair cognitive function or driving performance. However, further research is required to confirm these findings.
