Objective: Cannabidiol (CBD) is a non-intoxicating extract from Cannabis sativa. The advantages of CBD on sleep-wake cycle and insomnia remain sparse. The present study investigated the impact of a continuous four-week sublingual CBD intake on sleep indicators.

Materials and Methods: The present study was a randomized, double-blind, placebo-controlled, crossover pilot study involving 45 chronic insomnia patients. The participants were administered medium-chain triglycerides oil soluble cannabidiol (MCT-CBD) using 1 mg/kg/dose, sublingually for four weeks, then two weeks of washout period, and a subsequent four-week placebo phase. Sleep architecture with N1, N2, N3, and rapid eye movement (REM), sleep quality (PSQI), daytime sleepiness (ESS), and quality of life were investigated.

Results: Polysomnography (PSG) revealed that the total sleep time (TST), sleep onset latency (SOL), wake time after sleep onset (WASO), and arousal index were significantly improved compared to the patients who were taking placebo, while sleep structure remained unaltered. Additionally, actigraphy showed a substantial improvement in TST, sleep efficiency (SE), and SOL. The results of PSQI, ESS, and EQ-5D-5L were statistically

significant and better than placebo (p<0.05).

Conclusion: Continuously sublingual CBD treatment could improve sleep duration, sleep maintenance, sleep induction, quality of life, and daytime sleepiness without altering the sleep architecture in patients with chronic insomnia. No evidence of serious side-effects was found.