This was a randomized double-blind placebo-controlled crossover study published in December 2022 in the Journal of Sleep Research. 29 patients aged 25 to 75 years with clinical insomnia were included.
The researchers used a single product called Entoura-10:15 medicinal cannabis oil. "Participants were randomly allocated to receive placebo or active oil containing 10 mg/ml tetrahydrocannabinol (THC) and 15 mg/ml cannabidiol (CBD) over 2-weeks titrated 0.2–1.5 ml/day, followed by a 1-week wash-out period before crossover."
Crossover means those patients who took Entoura-10:15 during the first two weeks, then took placebo for the next two weeks (after a 1 week washout), and vice versa for the group that took placebo for the first two weeks.
So the maximum cannabinoid dose was approximately 15mg THC and 22.5mg CBD per day. Patients were instructed to ingest the oil with food, so it was swallowed, not tinctured under the tongue (oramucosal delivery).
Effectiveness was measured via:
- saliva midnight melatonin levels
- validated questionnaires (the Insomnia Severity Index)
- Fitbit activity/sleep wrist tracker
The authors' conclusions about the Entoura-10:15 oil:
The quality of sleep improved overall by up to 80% in the active group, including higher daily functioning
60% of participants no longer classified as clinical insomniacs at the end of the 2-week intervention period
Medicinal cannabis oil improved both time and quality of sleep, in particular light sleep increased by 21 min/night compared to placebo
Midnight melatonin levels significantly improved in the active group by 30% compared to a 20% decline in the placebo group
The full text research article is here at the Wiley Online Library.