A new study suggests that using marijuana before sleep has minimal if any effect on a range of performance measures the next day, including simulated driving, cognitive and psychomotor function tasks, subjective effects and mood. The results of the study indicated that a single oral dose of 10 mg THC (in combination with 200 mg CBD) does not notably impair ‘next day’ cognitive function or driving performance relative to placebo in adults with insomnia who infrequently use marijuana.
Cognitive tests were administered within two hours of participants waking, while driving performance, which was measured through a fixed-base driving simulator, was tested 10 hours after administration. Subjects were also asked about experienced effects—for example how “stoned,” “sedated,” “alert,” “anxious” or “sleepy” they felt—at baseline and then after 30 minutes, 10 hours, 12 hours, 14 hours, 16 hours and 18 hours. Answers differed for each participant, but the overall results were similar. 94% of the participants in the study who used marijuana before sleep, woke up in the morning feeling rested and more relaxed than on nights where they didn’t use cannabis. While alcohol leaves some people still tired and hungover in the morning which lead to impairment while driving, cannabis participants reported the opposite.