CBD has plenty of mechanistic interest and positive survey data, but the first proper RCT (DREAMLAND 2026, n=102, triple-blind) was negative — oral CBD did not beat placebo for post-surgical endo pain, and CBD had more adverse events. Survey data consistently shows 80%+ of users report pain relief, and animal models suggest CBD reduces endometriotic lesions and inflammation. ACOG concluded in 2024 that there is insufficient evidence to recommend cannabis products for gynaecological pain. The honest summary: plausible mechanism, popular in the community, but the first rigorous RCT disappointed.
Research status
Early Stage
Endo-specific
Partial
Community signal
Mixed
How does CBD work?
CBD targets multiple pathways implicated in endometriosis: it modulates the endocannabinoid system (CB1 and CB2 receptors), reduces pro-inflammatory cytokines (IL-6, TNF-alpha, IL-1-beta), inhibits angiogenesis (lowering VEGF and MMP expression), and has direct analgesic effects on nociceptive pathways. In rat and mouse endometriosis models, CBD reduces lesion size, peritoneal inflammation, and pain behaviours. THC (which is not pure CBD) adds additional CB1-mediated analgesia but also the psychoactive "high". The gap between the strong preclinical signal and the negative DREAMLAND RCT is not yet fully explained — possible reasons include placebo effects, dose or formulation limitations, or genuine lack of efficacy in humans.
What does the research show about CBD for endometriosis?
Below are studies linked to this intervention in our database, with design, quality, and outcomes summarised for quick scanning. Endo-specific evidence in this entry: Partial.
18 studies
Cannabidiol-Enriched Extract Oil for Postoperative Management of Chronic Pelvic Pain Secondary to Endometriosis: A Randomized Clinical Trial — DREAMLAND Study
Anelli GB et al. · 2026
RCTn=102Endometriosis-specificQuality: High
First triple-blind placebo-controlled RCT of CBD for endo pain. n=102 women with surgically treated endo and symptom recurrence. Oral CBD oil up to 150 mg/day for 10 weeks vs placebo. No between-group difference in pain reduction (both groups improved similarly; ~40% achieved >=50% pain reduction in each arm). Trial terminated early for futility. More adverse events in CBD group. Placebo group had better physical quality of life scores.
Cannabidiol-Enriched Extract Oil for Postoperative Management of Chronic Pelvic Pain Secondary to Endometriosis: A Randomized Clinical Trial — DREAMLAND Study
Anelli GB et al. · 2026
RCTn=102Endometriosis-specificQuality: High
First triple-blind placebo-controlled RCT of CBD for endo pain. n=102 women with surgically treated endo and symptom recurrence. Oral CBD oil up to 150 mg/day for 10 weeks vs placebo. No between-group difference in pain reduction (both groups improved similarly; ~40% achieved >=50% pain reduction in each arm). Trial terminated early for futility. More adverse events in CBD group. Placebo group had better physical quality of life scores.
A Longitudinal Assessment of Endometriosis Patients Prescribed Cannabis-Based Medicinal Products: A Case Series From the UK Medical Cannabis Registry
Getter S et al. · 2026
Observationaln=63Endometriosis-specificQuality: Medium
18-month prospective case series from UK Medical Cannabis Registry. Pain-specific and quality-of-life patient-reported outcomes improved significantly from baseline. ~80% prescribed dried flower alone or with oil at 18 months.
A Longitudinal Assessment of Endometriosis Patients Prescribed Cannabis-Based Medicinal Products: A Case Series From the UK Medical Cannabis Registry
Getter S et al. · 2026
Observationaln=63Endometriosis-specificQuality: Medium
18-month prospective case series from UK Medical Cannabis Registry. Pain-specific and quality-of-life patient-reported outcomes improved significantly from baseline. ~80% prescribed dried flower alone or with oil at 18 months.
Perceived impact of medicinal cannabis on pelvic pain and endometriosis related symptoms in Aotearoa New Zealand: an observational cohort study
Henry C et al. · 2026
ObservationalEndometriosis-specificQuality: Medium
Prospective mixed-methods cohort. Participants prescribed CBD oil alone or with dried cannabis flower; 12-week follow-up. Overall pelvic pain reduced from 5.46 to 3.77 on 10-point scale; worst pain from 7.62 to 5.38. Total EHP-30 score significantly improved. Limited adverse events. No placebo control.
Perceived impact of medicinal cannabis on pelvic pain and endometriosis related symptoms in Aotearoa New Zealand: an observational cohort study
Henry C et al. · 2026
ObservationalEndometriosis-specificQuality: Medium
Prospective mixed-methods cohort. Participants prescribed CBD oil alone or with dried cannabis flower; 12-week follow-up. Overall pelvic pain reduced from 5.46 to 3.77 on 10-point scale; worst pain from 7.62 to 5.38. Total EHP-30 score significantly improved. Limited adverse events. No placebo control.
Cannabidiol Use and Perceptions of Effectiveness in Women With Chronic Pelvic Pain
Till et al. · 2025
Observationaln=1,382Not endo-specificQuality: Medium
Cross-sectional survey of women with chronic pelvic pain + fibromyalgia. Of 477 current CBD users, 80.9% reported pain improvement. Those reporting pain relief also reported improved sleep, anxiety, depression, fatigue. About half had side effects, mostly minor (drowsiness most common). Many substituted CBD for higher-risk medications.
Cannabidiol Use and Perceptions of Effectiveness in Women With Chronic Pelvic Pain
Till et al. · 2025
Observationaln=1,382Not endo-specificQuality: Medium
Cross-sectional survey of women with chronic pelvic pain + fibromyalgia. Of 477 current CBD users, 80.9% reported pain improvement. Those reporting pain relief also reported improved sleep, anxiety, depression, fatigue. About half had side effects, mostly minor (drowsiness most common). Many substituted CBD for higher-risk medications.
Challenges in conducting a feasibility randomized controlled trial of medicinal cannabis for endometriosis pain in Australia
Chesterman S et al. · 2025
RCTn=12Endometriosis-specificQuality: Medium
Three-arm feasibility RCT (inhaled THC + oral CBD vs CBD alone vs placebo). Only 12 of 63 intended participants enrolled; 7 withdrew. Trial failed primarily due to required driving abstinence and high participant withdrawal rates, not efficacy concerns.
Challenges in conducting a feasibility randomized controlled trial of medicinal cannabis for endometriosis pain in Australia
Chesterman S et al. · 2025
RCTn=12Endometriosis-specificQuality: Medium
Three-arm feasibility RCT (inhaled THC + oral CBD vs CBD alone vs placebo). Only 12 of 63 intended participants enrolled; 7 withdrew. Trial failed primarily due to required driving abstinence and high participant withdrawal rates, not efficacy concerns.
What do people in online endo communities say about CBD?
Community signals are indicative only — they reflect informal conversation in endometriosis-focused spaces. People posting may or may not have a formal diagnosis; this is not a substitute for clinical evidence or care.
Reddit
Mixed · 2,500 mentions
HealthUnlocked
Mixed · 900 mentions
“CBD oil under the tongue at night actually helps me get to sleep through the cramps. Doesn't kill the pain but takes the edge off and stops me catastrophising about it.”
— Reddit
“Tried CBD for months, different brands, different strengths. Nothing. Switched to a CBD+THC product from a medical cannabis clinic and it was night and day. Pure CBD does basically nothing for me.”
— Reddit
“Be so careful where you buy from. The market is full of garbage. Look for a Certificate of Analysis or don't bother.”
— Reddit
“I've been on CBD oil 25mg twice a day for six months. Pain is genuinely better, especially the constant background ache between periods. Not a cure but a real improvement.”
— HealthUnlocked
“Got prescribed medical cannabis through Project Twenty21 in the UK. Game changer for the deep pelvic pain that no painkiller touched. CBD alone wasn't enough for me, needed the THC component.”
— HealthUnlocked
“Honestly tried it because I was desperate and it didn't do anything. Expensive too. Glad it works for some but didn't work for me.”
— HealthUnlocked
How is CBD typically used?
Practical notes
CBD is legal over the counter in most countries (UK, US, most of EU) as a food supplement at low doses. Quality varies enormously — products should be independently tested (look for a certificate of analysis). DREAMLAND used oral CBD oil up to 150 mg/day. Cross-sectional data suggests inhaled forms are rated more effective for acute pain relief, while oral forms are rated better for sleep, mood, and gastrointestinal symptoms. Side effects in the RCT were mild and gastrointestinal; CBD can also cause drowsiness, dry mouth, and appetite changes. CBD is metabolised by liver enzymes (CYP450) and can interact with many medications including hormonal contraceptives, SSRIs, and anticoagulants — check with a pharmacist. Medical cannabis (THC-containing) is available in Australia, Canada, and some US states but not legally prescribable for endometriosis in the UK. Cost: £30–£60/month typical for OTC CBD oil.
What should you know before trying CBD?
The first high-quality RCT (DREAMLAND 2026) failed to show CBD is superior to placebo. Also flagged: cost (£30–£60/month), drug interactions via CYP450, variable product quality in the unregulated OTC market, and potential adverse reproductive/fertility effects suggested by some in-vitro work.
Related interventions
Other interventions in our database that target similar symptoms or fall under the same category as CBD.