Summary: A recent real-world analysis indicates that cannabis-based medicinal products may provide sustained improvements in sleep for people with insomnia. In a cohort of 124 patients tracked for up to 18 months, participants reported better subjective sleep quality, reduced anxiety and depression symptoms, and improved overall quality of life. Side effects were generally mild and manageable. While randomized controlled trials are still required to establish definitive safety and efficacy, these findings highlight medical cannabis as a potential option when conventional treatments are insufficient.
The study found that many patients also experienced reductions in pain alongside improvements in sleep, and only a small portion reported adverse effects such as fatigue, dry mouth, or transient insomnia. No life-threatening or permanently disabling events were recorded. These outcomes suggest potential benefits of cannabis-based medicinal products for persistent insomnia, but confirmatory controlled trials are essential.
Key Facts
- Sustained sleep improvement: Participants reported better sleep quality that persisted over 18 months of treatment.
- Broader symptom relief: Scores for anxiety, depression, and pain-related measures also improved during follow-up.
- Generally mild side effects: Approximately 9% of patients reported non-serious effects such as fatigue, dry mouth, or brief insomnia episodes; no serious adverse events were recorded.
Source: PLOS
Insomnia patients treated with cannabis-based medicinal products reported improved sleep quality over periods up to 18 months, according to a study published August 27 in PLOS Mental Health by Arushika Aggarwal of Imperial College London and colleagues.
Insomnia is a common sleep disorder: roughly one in three people report occasional sleep difficulties, and about 10% of adults meet diagnostic criteria for an insomnia disorder. Standard treatments—cognitive-behavioural therapies and prescription sleep medications—can be difficult to access or carry risks such as dependence. This has increased interest in alternative and adjunctive approaches, including cannabis-based medicinal products.
To explore real-world outcomes, the research team analyzed data from 124 patients diagnosed with primary insomnia who were registered in the UK Medical Cannabis Registry. Participants completed validated patient-reported outcome measures (PROMs) at baseline and at intervals up to 18 months after starting treatment. The PROMs included a single-item Sleep Quality Scale (SQS), the Generalised Anxiety Disorder-7 (GAD-7) questionnaire, and the EQ-5D-5L measure for health-related quality of life.
Across follow-up time points—1, 3, 6, 12 and 18 months—participants reported meaningful improvements on the sleep quality scale compared with baseline. Anxiety symptoms measured by GAD-7 also showed statistically significant reductions at the same intervals. Measures of daily functioning and pain/discomfort drawn from the EQ-5D-5L similarly improved, reflecting gains in overall quality of life alongside better sleep.
Adverse events were recorded and classified using standard criteria. Eleven participants (8.9%) reported side effects totaling 112 events; the most commonly reported complaints were fatigue, dry mouth, and transient worsening of sleep in a small number of cases. Importantly, no events were disabling or life-threatening, and the authors describe the treatment as generally well tolerated within this observational dataset.
Despite encouraging real-world signals, the authors emphasize that randomized controlled trials remain the gold standard for establishing causal efficacy and long-term safety of cannabis-based medicinal products for insomnia. Observational registry data offer valuable insight into real-world patient experiences, but are subject to confounding factors and cannot replace controlled experimental evidence.
Co-author Dr. Simon Erridge, Research Director at Curaleaf Clinic, noted that the 18-month follow-up provided valuable longitudinal information beyond what short-term trials typically capture. He highlighted sustained improvements in subjective sleep quality and anxiety, while also pointing out potential signs of tolerance in some patients—underscoring the need for individualized dosing, ongoing monitoring, and further research.
About this psychopharmacology and insomnia research news
Author: Charlotte Bhaskar ([email protected])
Source: PLOS
Contact: Charlotte Bhaskar – PLOS
Image: Image credited to Neuroscience News
Original Research: Open access. “UK Medical Cannabis Registry: A clinical outcomes analysis for insomnia” by Arushika Aggarwal et al. PLOS Mental Health. DOI: 10.1371/journal.pmen.0000390
Abstract
UK Medical Cannabis Registry: A clinical outcomes analysis for insomnia
Insomnia affects around 10% of adults globally and is associated with impaired daytime function, mood disturbance, and reduced quality of life. Conventional pharmacological and non-pharmacological treatments have limitations, creating interest in the potential role of cannabis-based medicinal products for certain patients.
This observational case-series examined changes in sleep-specific and general patient-reported outcome measures in individuals prescribed cannabis-based medicinal products for primary insomnia, using data from the UK Medical Cannabis Registry. Outcomes assessed included the Single-Item Sleep Quality Scale (SQS), Generalised Anxiety Disorder-7 (GAD-7), and the EuroQol-5 Dimension-5 Level (EQ-5D-5L). PROMs were compared from baseline to 1, 3, 6, 12 and 18 months. Adverse events were categorized according to CTCAE v4.0.
A total of 124 participants met inclusion criteria. Mean SQS scores improved significantly from baseline (2.66 ± 2.41) to each follow-up: 1 month (5.67 ± 2.65), 3 months (5.41 ± 2.69), 6 months (4.80 ± 2.89), 12 months (4.24 ± 3.01) and 18 months (3.81 ± 2.90), all p < 0.001. GAD-7 scores showed statistically significant improvement at the same intervals (p < 0.05). EQ-5D-5L dimensions for usual activities, pain/discomfort, and anxiety/depression, along with index values, also improved (p < 0.001).
Eleven participants (8.87%) reported adverse events, totaling 112 events; the vast majority were non-serious and none were disabling or life-threatening. The study concluded that, within this registry cohort, treatment with cannabis-based medicinal products was associated with improvements in subjective sleep quality and related patient-reported outcomes. The authors recommend randomized controlled trials to confirm these observational findings and to establish long-term efficacy and safety.