About a third of endometriosis patients using cannabis reported side effects, but some of those effects might actually be helpful | Research

The takeaway

In an international survey of people with endometriosis using cannabis, 32% reported side effects, but the researchers argue some commonly labeled adverse effects (like appetite changes and sedation) may have therapeutic value for this population.

People with endometriosis considering cannabis, clinicians counseling patients on cannabis use, and researchers studying patient-reported outcomes.

32% reported side effects, some potentially therapeutically useful

What the researchers found

Among endometriosis patients using cannabis for symptom management, 32% experienced side effects, consistent with published literature. However, the study suggests that some reported adverse effects may have clinical utility in the endometriosis population and require more nuanced interpretation.

Why it matters

Endometriosis patients are increasingly turning to cannabis for pain management, often without medical guidance. Reframing certain "side effects" as potentially beneficial challenges the binary categorization of drug effects and could inform more patient-centered care.

The numbers in context

889 participants in the larger survey. 32% of cannabis users reported side effects. The study was a subset analysis examining whether reported adverse effects have therapeutic relevance.

How the study worked

Subset analysis of a larger international survey (n=889) investigating self-reported effectiveness, safety, and pharmaceutical de-prescribing trends of cannabis use among people with endometriosis.

What this study cannot tell us

Survey-based self-reported data. Subset of a larger study, so the specific sample size for this analysis is unclear. No clinical verification of endometriosis diagnosis or cannabis use. International sample with varying legal and product quality contexts.

How to read the evidence

Preliminary: survey-based subset analysis with self-reported data and no clinical verification.

When this study was published

Published 2026.

The bigger picture

The concept that a side effect in one context can be therapeutic in another is well-established in medicine (sedation as a side effect vs. a sleep aid). This study applies that lens to cannabis use in endometriosis, where symptoms like poor appetite, insomnia, and anxiety often co-occur with pain.

Questions still open

Which specific cannabis side effects do endometriosis patients find beneficial? Does the therapeutic reframing of side effects change prescribing or counseling practices? How do these patterns differ by cannabis product type?

Common questions

Do people with endometriosis experience side effects from cannabis?

About 32% reported side effects in this international survey, a rate consistent with the broader cannabis literature.

Can cannabis side effects be beneficial for endometriosis patients?

The researchers suggest that effects typically labeled as adverse, such as appetite changes and sedation, may actually address co-occurring endometriosis symptoms.

Read the original research

Cannabis and Endometriosis: When Is an Adverse Effect Not Adverse?

The Australian & New Zealand journal of obstetrics & gynaecology, 66(1), e70076

View on PubMed ↗Publisher’s paper ↗

Citation

Sinclair, Justin; Adler, Hannah; Eathorne, Allie; Holtzman, Orit; Ee, Carolyn; Abbott, Jason; Sarris, Jerome; Armour, Mike. (2026). Cannabis and Endometriosis: When Is an Adverse Effect Not Adverse?. The Australian & New Zealand journal of obstetrics & gynaecology, 66(1), e70076. https://doi.org/10.1111/ajo.70076