Endometriosis in the UK
Endometriosis is a chronic, systemic inflammatory condition in which tissue similar to the uterine lining grows outside the uterus, commonly on the ovaries, fallopian tubes, bowel, bladder, and peritoneum. It affects an estimated 1.5 million women of reproductive age in the UK and is one of the most prevalent and consistently under-diagnosed gynaecological conditions in the world. The average time from onset of symptoms to diagnosis in the UK is eight to twelve years.
The core symptom is pain: dysmenorrhoea affecting up to 90% of patients; chronic pelvic pain; deep dyspareunia; and painful bladder or bowel symptoms. The economic cost to the UK has been estimated at 8.2 billion pounds annually. Current treatments are inadequate for a substantial proportion of patients, driving widespread patient interest in medical cannabis as an alternative or complement to existing therapies.
The Endocannabinoid System and Endometriosis
The endocannabinoid system is deeply integrated into normal reproductive physiology. CB1 and CB2 receptors are expressed throughout the female reproductive tract. Studies have identified reduced CB1 receptor expression in peritoneal nerve fibres innervating endometriotic lesions, a finding that may explain why normal endocannabinoid tone is insufficient to suppress pain in the condition. CB2 receptors, expressed on immune cells that infiltrate endometriotic tissue, represent a promising target for reducing the inflammatory microenvironment surrounding lesions.
Evidence for Medical Cannabis in Endometriosis
- A 2020 qualitative study found that 13% of women with endometriosis reported using cannabis for symptom management, with the majority rating it as highly effective for pain and nausea.
- A large 2021 survey of 484 Australian women with endometriosis found that self-reported cannabis use was associated with significant reductions in pain scores, nausea, and depression. Cannabis was rated the most effective pain management strategy by respondents.
- Preclinical research from Syracuse University has demonstrated that endocannabinoid system activation reduces endometriotic lesion size, vascularisation, and associated pain behaviour in animal models.
Symptoms Medical Cannabis May Help
Based on current evidence and clinical experience:
- Chronic pelvic pain — both inflammatory and neuropathic components respond to cannabinoid analgesia
- Dysmenorrhoea — THC-mediated uterine muscle relaxation and CB1-mediated pain modulation may reduce period pain severity
- Nausea and gastrointestinal symptoms — cannabinoids are established antiemetics and may reduce endometriosis-related bowel symptoms
- Sleep disturbance — pain-driven insomnia responds to combined analgesic and sedative cannabinoid properties
- Anxiety and depression — common comorbidities in endometriosis that respond to CBD and balanced formulations
UK Prescribing Pathway
To access medical cannabis for endometriosis pain in the UK, a specialist assessment is required, typically with a gynaecologist experienced in endometriosis management or a specialist pain physician. Documentation of a confirmed or strongly suspected endometriosis diagnosis and evidence that conventional treatments have been inadequate will be required.
Medical cannabis is contraindicated in pregnancy and for those actively trying to conceive. Cannamedical Britannia offers EU-GMP certified cannabis-based medicines across a range of formulations, including CBD-dominant oils suitable for daytime use without psychoactive effects, and balanced THC:CBD options for evening pain and sleep management.