Endometriosis and inflammation

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.

Dienogest is a daily 2 mg progestin tablet developed specifically for endometriosis and licensed for that purpose across Europe, Japan, much of Asia, Latin America, and (since 2024) Australia. The evidence base for pain reduction is among the strongest of any endometriosis treatment, but a meaningful minority of people stop because of mood changes, irregular bleeding, or other progestin side effects.

Naproxen is widely recommended as first-line medication for endo-associated pain by ACOG, NICE, ESHRE and others, with strong evidence for menstrual pain generally but surprisingly thin endo-specific evidence. The 2015 Cochrane review of 80 RCTs confirmed NSAIDs significantly outperform placebo for primary dysmenorrhoea. For endo specifically, the 2017 Cochrane review found only one small RCT (Kauppila 1985) and concluded evidence was insufficient — not because NSAIDs don't work, but because they've never been properly tested in endo. Naproxen has mid-range GI risk among NSAIDs (higher than ibuprofen, lower than ketorolac). Take with food, ideally before period onset, and consider adding a PPI for regular use.

Omega-3 has a split evidence picture. For primary dysmenorrhoea, multiple meta-analyses show moderate-to-large pain reduction with supplementation. For endometriosis specifically, a 2025 meta-analysis of 5 RCTs found no significant pain benefit — despite a clear reduction in inflammatory markers. The SAGE RCT (2020) in adolescents with endo actually found fish oil did slightly worse than placebo. Observational data suggests higher dietary omega-3 may lower endo risk. Low-risk and good for general health, but don't expect dramatic pain reduction. Typical effective doses in dysmenorrhoea trials: 300-1800mg EPA+DHA daily, with lower doses counterintuitively more effective.