Can Medical Cannabis Help with Sleep Disorders?

Poor sleep is a significant public health issue in the UK. The Sleep Council estimates that around one in three people suffer from poor sleep, and the NHS reports that insomnia affects approximately 30% of the adult population at some point in their lives.

Conventional treatments include sleep hygiene advice, cognitive behavioural therapy for insomnia (CBT-I), and medications such as benzodiazepines and Z-drugs. While effective for many, these medications carry risks of dependence and tolerance, and many patients seek alternatives.

The relationship between cannabis and sleep is complex. THC has sedative properties and can reduce the time it takes to fall asleep (sleep latency). However, it also suppresses REM sleep — the stage associated with dreaming and memory consolidation — which may have long-term implications with heavy use.

CBD, by contrast, appears to have a more nuanced effect on sleep. At lower doses, CBD may have alerting properties; at higher doses, it appears to promote sleep. CBD also reduces anxiety, which is a major driver of insomnia in many patients.

The evidence for CBMPs specifically in sleep disorders is still emerging, but several findings are encouraging:

• A 2019 study in The Permanente Journal found that CBD significantly improved sleep scores in 66.7% of patients within the first month of treatment.

• The UK Medical Cannabis Registry has reported improvements in sleep quality as one of the most consistent patient-reported outcomes across multiple conditions.

• Patients with PTSD — for whom nightmares and sleep disturbance are core symptoms — have shown particularly strong responses to CBMPs in several observational studies.

• A 2021 review in Current Psychiatry Reports concluded that cannabinoids show promise for improving sleep in patients with chronic pain, PTSD, and anxiety disorders.

Based on the available evidence, the patients most likely to benefit from CBMPs for sleep disorders are those whose sleep problems are secondary to another condition, such as:

• Chronic pain — pain-related sleep disruption is one of the most common presentations
• PTSD and anxiety — hyperarousal and nightmares respond well to CBD-dominant preparations
• Multiple sclerosis — spasticity and pain at night are major contributors to poor sleep in MS
• Primary insomnia — where conventional treatments have failed

Patients with primary insomnia without an underlying condition may also benefit, though the evidence is less robust in this group.

For sleep disorders, clinicians typically prescribe CBD-dominant preparations, often with a small amount of THC to enhance the sedative effect (known as the entourage effect). Common formulations include sublingual oils (taken under the tongue before bed) and capsules.

Dried flower for vaporisation is sometimes prescribed for patients who need rapid onset of effect. However, this route of administration is less commonly used for sleep disorders due to the difficulty in titrating the dose precisely.

If you believe you may benefit from CBMP treatment for a sleep disorder, the first step is to register as a patient with MEDCANN Pharmacy. Our specialist clinicians will assess your eligibility, review your medical history, and discuss whether a CBMP prescription is appropriate for your situation.

You will need to have tried conventional treatments first — including sleep hygiene advice and at least one medication — before a CBMP prescription can be considered. However, if you have been struggling with sleep for a significant period and conventional approaches have not worked, you may well be eligible.