Overview
- The PLOS Mental Health study followed 124 adults with primary insomnia from the UK Medical Cannabis Registry who used study-supplied oil or dried flower under a controlled daily regimen with no outside cannabis allowed.
- Participants reported the largest sleep-quality improvement in the first month, with gains persisting but declining at 12 and 18 months, alongside early improvements in anxiety, depression, and pain.
- About 8.9% of patients reported adverse events such as fatigue, dry mouth, or insomnia, with no disabling or life-threatening cases recorded.
- Dosing data showed rising exposure over time, with median daily THC increasing from 20 mg at baseline to 120 mg at 18 months and a modest CBD uptick, suggesting possible tolerance to therapeutic effects.
- Authors noted many participants had previously failed at least two licensed sleep medications and said medical cannabis may have a role in refractory cases pending confirmation in randomized controlled trials.