Journal Club: Sleep and cannabis-based medicines

The latest issue of the Journal Club explores the benefits of cannabis-based medicines for sleep and insomnia.

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For this edition of the journal club, the focus is on sleep. There is abundant anecdotal evidence supporting the soporific effect of cannabis, with sufferers from a range of conditions reporting that it assists in the management of insomnia [1,2].

Additionally, somnolence is a commonly listed adverse event (AE) in clinical trials involving cannabis-based medicinal products (CBMPs).

However, to date, most of the evidence has been gathered from CBMP studies focusing on chronic pain that include sleep as a secondary end-point. In this issue of the Journal Club, two recent clinical trials are highlighted that specifically investigate the effect of CBMPs in patients with insomnia.

The first study is a randomised, double-blind, placebo-controlled trial evaluating the safety and efficacy of nightly administration of a sublingual cannabinoid extract (ZTL-101 – a 20:1 THC:CBD preparation) in 23 patients with chronic insomnia. The placebo contained the same terpenes as ZTL-101 (in order to match smell, taste, and colour), but no cannabinoids.This was a crossover design so the 23 patients in the study took either ZTL-101 or placebo for a period of two weeks and then – following a one-week washout period – switched to the other treatment for a further two weeks.

Insomnia symptoms were assessed using the Insomnia Severity Index (ISI). Overall, ISI scores at the end of two weeks were significantly lower with ZTL-101 than with placebo. Compared to placebo, ZTL-101 also decreased self-reported sleep onset latency, and increased total sleep time, sleep quality, and the feeling of being rested on waking. No serious AEs [adverse effects] were reported. Forty mild AEs were reported (36 during ZTL-101), with the majority being headache, dizziness, and dry mouth.

In summary, this study demonstrated that nightly sublingual administration of a THC-predominant extract for two weeks improved insomnia symptoms and sleep quality relative to placebo without significant AEs in patients with chronic insomnia. 

The second study is a naturalistic, retrospective trial investigating the use profile and perceived efficacy of cannabinoids for the management of insomnia.

Data was collected using the Strainprint app, which allows users to log and monitor their symptoms pre- and post-cannabis use. In total, the study examined 991 medical cannabis users with insomnia across 24,189 tracked cannabis use sessions.

Overall, cannabinoids were perceived to be efficacious across all genders and ages, and no significant differences were found among ingestion methods. Although all product categories were perceived as efficacious, predominant Indica strains were found to reduce insomnia symptomology more than predominant sativa strains and CBD-predominant formulations.

In summary, this study showed that medical cannabis users perceive a significant improvement in insomnia with cannabinoid use, with indica strains being reported as more effective than sativa strains or CBD alone. This emphasises the importance of both THC and terpene content in maximising outcomes for patients with insomnia.

If you are a doctor and would like to discuss either of the clinical papers featured in this edition of the journal club or the broader medical cannabis literature, please reach out on luca.marelli@growbiotech.com

Read more from the Journal Club here

References:

1 Bonn Miller.M, Babson.K, Vandrey.R. Using cannabis to help you sleep: heightened frequency of medical cannabis use among those with PTSD (2014). Drug Alcohol Depend 136:162-5

2 Russo.E, Guy.G, Robson.P. Cannabis, pain, and sleep: lessons from therapeutic clinical trials of Sativex, a cannabis-based medicine (2007). Chem Biodivers 4(8):1729-1743