Medical Cannabis for Endometriosis: A Guide for UK Patients

Understanding Endometriosis and Its Impact

Endometriosis is a chronic gynaecological condition in which tissue similar to the lining of the uterus grows outside the womb — on the ovaries, fallopian tubes, bowel, or bladder. It affects approximately 1 in 10 women of reproductive age in the UK, equating to around 1.5 million people, yet the average time from symptom onset to diagnosis remains a staggering 8 years.

The condition causes severe pelvic pain, particularly during menstruation, painful intercourse, bowel and bladder symptoms, and in many cases, fertility problems. The chronic, cyclical nature of the pain can be profoundly disabling, affecting work, relationships, and mental health.

Conventional treatments — including hormonal therapies such as the combined pill or GnRH analogues, and surgical intervention — are not effective for all patients and often carry significant side effects. This has led many women with endometriosis to explore alternative pain management strategies, including cannabis-based medicinal products.

What Does the Research Show?

Evidence for medical cannabis in endometriosis is growing. A 2025 case series from the UK Medical Cannabis Registry examined outcomes in patients with endometriosis prescribed CBMPs, finding associations with improvements in pain scores and health-related quality of life. The researchers noted reductions in both pelvic pain intensity and pain interference with daily activities.

The biological rationale is compelling. The endocannabinoid system is known to play a role in pain modulation, inflammation, and the regulation of the immune response — all of which are disrupted in endometriosis. Cannabinoid receptors (CB1 and CB2) have been identified in endometriotic lesions themselves, suggesting that the endocannabinoid system may be directly involved in the pathophysiology of the condition.

THC and CBD may work together to reduce the neuroinflammatory signalling that drives chronic pelvic pain, while also addressing the anxiety, sleep disruption, and mood disturbance that so commonly accompany endometriosis.

Is Medical Cannabis Available for Endometriosis in the UK?

Yes. Endometriosis is a condition for which specialist doctors in the UK can prescribe cannabis-based medicinal products on a private basis. As with other conditions, NHS prescriptions remain rare, and most patients access CBMPs through private specialist clinics.

Eligibility typically requires a confirmed diagnosis of endometriosis and evidence that conventional pain management approaches (such as NSAIDs, hormonal therapy, or surgical intervention) have not provided adequate relief. A specialist doctor will assess your individual circumstances before prescribing.

What Forms of Medical Cannabis Are Used?

For endometriosis, patients are most commonly prescribed cannabis oil (taken sublingually under the tongue) or, in some cases, dried flower for vaporisation. Oils offer precise dosing and a slower onset, making them suitable for managing background pain. Vaporised flower has a faster onset and may be more useful for acute pain flares.

The appropriate THC:CBD ratio varies between patients. Some find that CBD-dominant formulations provide adequate anti-inflammatory and analgesic effects; others require higher THC content for adequate pain relief. Your prescribing doctor will guide you through the titration process.

How CPGUK Can Help

CPGUK is a non-profit organisation dedicated to helping UK patients navigate access to medical cannabis. If you are living with endometriosis and struggling to manage your pain, we can help you understand your options, connect you with specialist clinics, and support you through the process of obtaining a private prescription. Our service is entirely free and confidential.