A study published in Addiction examined the effects of cannabidiol (CBD) on visual function and driving performance. Analysis of clinical trial data revealed no evidence of significant changes in driving performance.
The study at the University of Granada’s Laboratory of Vision Sciences and Applications assessed participants’ driving performance after inhaling CBD or a placebo. The research team recruited 30 participants from the local and university community. The participants possessed valid driving licenses and reflected a mean age of 26. All participants used CBD or cannabis occasionally and held valid driving licenses.
The participants engaged in three experimental sessions conducted one week apart. The team administered vaporizing products to participants containing either a placebo, 15% percent CBD (16 mg), or 30 % CBD (32 mg) to participants. The researchers assessed the participants’ overall driving performance score (ODPS) and visual function variables such as motion detection, contrast sensitivity, stereo acuity, and static and dynamic visual acuity. The research team also documented driving performance parameters such as reaction time, mean speed, and lateral vehicle control.
The participants did not demonstrate statistically significant changes in the overall driving performance score. The researchers also noted no statistically significant differences in secondary outcomes, such as reaction time, distance traveled outside the lane, standard deviation of lateral lane position, or collisions. The findings also indicated no significant effects on visual functions following CBD consumption.
The study suggests consuming CBD before engaging in vision-dependent tasks such as driving is relatively safe. The researchers suggest that further studies should examine the effects of higher doses of CBD. Higher doses of CBD can cause drowsiness for some consumers, so it is critical future research explores effects relative to dosing levels and other modes of administration, such as oral consumption of CBD oil or infused edibles.