Cluster Headaches and Medical Cannabis: The Facts
Patients are up to
18 times
more likely to suffer from cluster headaches if a first-degree relative experiences them [1].
What Causes Cluster Headaches?
The exact cause of cluster headache is not fully understood. Research suggests the hypothalamus, the part of the brain that regulates sleep and biological rhythms, may play a role. This may explain why attacks often follow a pattern and can occur at similar times each day.
Cluster headache also involves the trigeminal nerve, which carries pain signals from the face to the brain.
Risk factors include:
- Family history
- Male sex
- Smoking
- Previous head injury
During an active cluster period, certain triggers may provoke attacks, including:
- Alcohol
- Strong smells (such as petrol or perfume)
- Overheating
- Some medications
Triggers do not cause the condition itself but may increase the likelihood of an attack during a cluster cycle.
What are the Symptoms of Cluster Headaches?
Cluster headache is characterised by severe, one-sided pain, usually around the eye or temple. The pain is often described as burning, piercing or stabbing and can be extremely intense.
Attacks typically last between 15 minutes and three hours.
Additional symptoms may include:
- Red or watering eye on the affected side
- Drooping or swelling of the eyelid
- Smaller pupil on the affected side
- Blocked or runny nostril
- Facial sweating
- Restlessness or pacing during attacks
Unlike migraine, people with cluster headache often feel unable to lie still during an episode.
Can Cluster Headache be Treated?
Over-the-counter painkillers are often ineffective for cluster headache. Instead, treatment focuses on rapid relief during attacks and preventative therapy during cluster periods.
Acute treatments (during an attack)
- High-flow oxygen therapy via face mask
- Triptan injections or nasal sprays
Oxygen is thought to work by narrowing widened blood vessels and reducing trigeminal nerve activity during an attack.
Preventative treatments
- Verapamil (a calcium-channel blocker)
- Short courses of corticosteroids
- Other specialist medications in selected cases
For people with chronic cluster headache, preventative treatment may be needed long term.
How do Cluster Headache Affect People?
Cluster headache can be highly disruptive. Attacks frequently occur at night, interrupting sleep and contributing to fatigue.
The severity and unpredictability of cluster cycles can affect work, social life and mental wellbeing. Some people experience anxiety about when the next attack may occur.
A comprehensive care plan aims to reduce attack frequency, manage pain effectively and support overall quality of life.
"I heard about Curaleaf Clinic from a close friend. I felt that I was listened to, and the different types of pain I was experiencing was understood and my treatment plan was tailored to suit my individual needs”.
Medical Cannabis for Cluster Headaches
Cluster headache can be challenging to manage for some individuals. In certain circumstances, medical cannabis may be considered as part of a broader specialist pain management approach, particularly where symptoms continue to significantly impact daily life despite standard treatment.
Since 2018, specialist doctors on the GMC Specialist Register have been legally permitted to prescribe medical cannabis in the UK. Prescribing decisions are made following a full clinical assessment and are based on an individual’s medical history, current symptoms and previous treatments.
Medical cannabis is not a first-line treatment for cluster headache and is not suitable for everyone.
Research Regarding Medical Cannabis and Cluster Headaches
Research into medical cannabis for cluster headache is still developing, and much of the current understanding comes from real-world clinical practice.
Data from the UK Medical Cannabis Registry has included patients with primary headache disorders, including cluster headache. In one observational analysis of 97 patients with headache conditions, approximately 9% had cluster headache as their primary diagnosis. [3]
During follow-up, patients reported changes in headache severity and overall quality of life. Side effects were also recorded, most commonly dry mouth, fatigue and changes in concentration. The majority of reported adverse effects were described as mild.
As this was an observational study, it cannot establish cause and effect. However, real-world evidence plays an important role in understanding how treatments are used in specialist clinical practice, particularly in conditions where large-scale trials remain limited.
In the UK, specialist doctors on the GMC Specialist Register are permitted to prescribe medical cannabis where they believe it may be clinically appropriate following a full assessment. Prescribing decisions are made on an individual basis, taking into account a patient’s medical history, previous treatments and current symptoms.
Can I be Prescribed Medical Cannabis for Cluster Headaches?
If you are exploring further treatment options for cluster headache, you can complete an initial eligibility assessment with Curaleaf Clinic. Your medical history and previous treatments will be reviewed, and if appropriate, you may be invited to meet with a clinician experienced in headache and pain management.
We understand how disruptive cluster headache can be, and our role is to provide clear information and specialist guidance so you can decide what feels right for you.
References
[1] Sandor, P. S., Irimia, P., Jager, H. R., Goadsby, P. J., & Kaube, H. (2006). Onset of cluster headache triggered by emotional effect: a case report. Journal of neurology, neurosurgery, and psychiatry, 77(9), 1097–1099. https://doi.org/10.1136/jnnp.2005.087247
[2] Andre, L., & Cavers, D. (2021). ‘A cry in the dark’: a qualitative exploration of living with cluster headache. British journal of pain, 15(4), 420–428. https://doi.org/10.1177/2049463720976695
[3] Nicholas M, Erridge S, Bapir L, Pillai M, Dalavaye N, Holvey C, Coomber R, Rucker JJ, Weatherall MW, Sodergren MH. UK medical cannabis registry: assessment of clinical outcomes in patients with headache disorders. Expert Rev Neurother. 2023 Jan;23(1):85-96. doi: 10.1080/14737175.2023.2174017. Epub 2023 Feb 3. PMID: 36722292.