Cannabinoids have been proposed as a potential new therapeutic alternative for treating chronic insomnia.
The aim of the world-first randomized double-blind placebo-controlled crossover trial led by Jennifer Walsh from the University of Western Australia, Centre for Sleep Science was to evaluate the safety and efficacy of medical cannabis for treating insomnia symptoms. Patients with chronic insomnia disorder were characterized by difficulty initiating or maintaining sleep at least 3 nights per week for at least 3 months.
In this study, patients were either treated with medical cannabis or placebo. Patients were randomly allocated to medical cannabis or placebo for 2 weeks (randomization). Both participants and investigators were blind to whether medical cannabis or placebo was administered (double-blind study design), which is in accordance with clinical-scientific standards.
They found that two weeks of medical cannabis significantly decreased insomnia symptoms relative to placebo. Patients perceived that they went to sleep faster, slept for longer, had improved sleep quality, and felt more rested/refreshed on waking.
The researchers also found that no serious adverse events were reported during medical cannabis dosing. All adverse events, such as dry mouth or dizziness, were classified as mild and had either resolved overnight or soon after waking.
Two weeks of nightly sublingual administration of a cannabinoid extract was well tolerated and improved insomnia symptoms and sleep quality in individuals with chronic insomnia symptoms. No serious adverse events were reported.
The significant improvements in self-reported measures of sleep were also seen in objective measures, such as actigraphy.
Following a single dose of the cannabinoid extract, peak plasma levels of the major constituents were reached at approximately 4-6 hours. Data suggest that for patients with sleep onset insomnia dosing 2-4 hours before desired bedtime might be optimal, while those with sleep maintenance insomnia should dose 1 hour before desired bedtime.
Walsh JH, Maddison KJ, Rankin T, Murray K, McArdle N, Ree MJ, Hillman DR, Eastwood PR. Treating insomnia symptoms with medicinal cannabis: a randomized, crossover trial of the efficacy of a cannabinoid medicine compared with placebo. Sleep 2021:zsab149.