Medical Cannabis Linked to Lasting Relief and Lower Opioid Use in Endometriosis Patients

Medical Cannabis May Ease Endometriosis Pain and Reduce Opioid Use

For millions of people living with endometriosis, pain is not limited to a difficult day or an uncomfortable menstrual cycle. It can become a chronic, life-altering condition that disrupts sleep, work, relationships, mental health, and quality of life.

New real-world research offers a hopeful reason to study medical cannabis more seriously. In a two-year analysis from the UK Medical Cannabis Registry, endometriosis patients reported sustained improvements in pain, sleep, anxiety, and health-related quality of life after beginning treatment with cannabis-based medicinal products. The study also documented a reduction in prescribed opioid use.

The findings were originally reported by National NORML, whose continued coverage of cannabis science helps patients, advocates, and policymakers follow an evidence base that is too often overlooked.

What Is Endometriosis?

Endometriosis is a chronic inflammatory condition in which tissue similar to the lining of the uterus grows outside the uterus. It can cause severe pelvic pain, painful periods, pain during sex, gastrointestinal symptoms, fatigue, and fertility problems.

The condition affects up to 10 percent of females of reproductive age, yet diagnosis can take years and available treatments do not work for everyone. Treatment may involve pain medication, hormonal therapies, and surgery. Some patients continue to experience substantial pain despite trying several conventional options.

That gap between what patients need and what medicine can consistently provide is one reason cannabis for endometriosis pain has become an important area of research.

What Did the Medical Cannabis Study Examine?

The study, titled “Cannabis-Based Medicinal Products for Endometriosis: A 2-Year Prospective Analysis From the UK Medical Cannabis Registry,” was published in the Australian and New Zealand Journal of Obstetrics and Gynaecology.

Researchers followed 101 adult women with a primary diagnosis of endometriosis who were enrolled in the UK Medical Cannabis Registry. Participants received prescribed cannabis-based medicinal products, which could include cannabis flower, oil extracts, or topical preparations.

Researchers compared patient-reported outcomes at the beginning of treatment with follow-up measurements collected after one, three, six, 12, 18, and 24 months. They assessed:

• Pain severity and the degree to which pain interfered with daily life

• Health-related quality of life

• Sleep quality

• Anxiety

• Prescribed opioid burden

• Adverse events

This long follow-up period is significant because chronic conditions require more than short-lived symptom relief. Patients need to know whether improvements may persist over time.

Patients Reported Improvements That Lasted Two Years

Participants reported improvements across multiple measures of pain, daily functioning, quality of life, sleep, and anxiety. These improvements were observed throughout the study and remained evident at the 24-month follow-up.

That does not mean medical cannabis cured endometriosis. It means that, among this group of patients, cannabis-based medicines were associated with sustained relief from several of the symptoms that can make the condition so difficult to live with.

The breadth of the reported improvements is particularly notable. Chronic pelvic pain does not exist in isolation: it can keep someone awake, increase anxiety, restrict physical activity, and interfere with work and relationships. A treatment that may help several connected quality-of-life measures deserves careful attention.

Prescribed Opioid Use Also Declined

The study also found that average prescribed oral morphine equivalents decreased from 19.9 milligrams per day at baseline to 14.8 milligrams per day after 24 months. More than one-quarter of participants achieved a clinically significant reduction in prescribed opioids at the two-year mark.

This finding should not be interpreted as advice to abruptly stop opioid medication. Opioid changes should be managed with a qualified healthcare professional, because sudden discontinuation can cause withdrawal and other serious problems.

Still, the result matters. Opioids can provide pain relief, but long-term use may involve tolerance, dependence, adverse effects, and overdose risk. If cannabis-based medicines can help some endometriosis patients manage symptoms while reducing their reliance on opioids, that possibility warrants rigorous investigation.

What About Side Effects?

Eighteen participants, or 17.8 percent of the study group, reported a total of 165 adverse events. About half of the reported events were classified as mild. The most frequently reported effects included fatigue, lethargy, and headache.

The researchers described the overall adverse-event profile as favorable, but “well tolerated” does not mean risk-free. Cannabis may cause impairment, dizziness, anxiety, sedation, or interactions with other medications. Products containing THC can affect driving and other safety-sensitive activities.

Patients considering medical cannabis should discuss their health history, current medications, pregnancy status, and treatment goals with a qualified clinician.

What the Study Can—and Cannot—Prove

These findings are promising, but they must be understood in context. This was an observational registry study. Researchers followed patients receiving prescribed cannabis products in real-world practice; they did not randomly assign participants to cannabis and placebo groups.

As a result, the study shows an association between medical cannabis treatment and improved outcomes, but it cannot prove that cannabis alone caused every improvement. Other treatments, patient expectations, changes in health, and the natural fluctuation of symptoms may also have influenced the results.

The study also relied on patient-reported outcomes and included a relatively small group of 101 participants. Different cannabis formulations, cannabinoid ratios, doses, and routes of administration may produce different results.

The next step should be larger randomized controlled trials that can better determine effectiveness, safety, dosing, and which patients are most likely to benefit.

Why This Research Matters in Florida

Endometriosis is not currently listed as a stand-alone qualifying condition in Florida’s medical marijuana law. However, Florida physicians may certify patients for conditions of the “same kind or class as or comparable to” specifically listed qualifying conditions when the physician determines that the potential benefits outweigh the risks.

That makes physician education and patient access especially important. No Floridian should have to rely on stigma, guesswork, or unregulated claims when making decisions about a serious chronic condition. Patients deserve honest information, regulated products, medical guidance, and policies that allow doctors to evaluate cannabis using the same evidence-based principles applied to other treatments.

Research like this also underscores why cannabis policy is a healthcare issue. Federal restrictions have slowed clinical research and complicated access for decades. Reform should make it easier—not harder—to conduct high-quality studies and give patients informed choices.

The Bottom Line

This two-year UK registry study adds meaningful real-world evidence to the discussion of medical cannabis for endometriosis. Patients reported sustained improvements in pain, sleep, anxiety, and quality of life, while prescribed opioid burden declined and reported cannabis-related adverse events were generally mild or moderate.

The results are encouraging, but they are not the final word. Medical cannabis should not be described as a proven cure for endometriosis, and observational evidence should not be mistaken for randomized clinical proof. What the study does show is that cannabis-based medicine deserves deeper investigation as a potential component of individualized endometriosis care.

Suncoast NORML thanks National NORML for its original reporting on this study and for continuing to make emerging cannabis research accessible to the public.

Medical disclaimer: This article is for educational and informational purposes only and is not medical advice. Do not begin cannabis treatment or change prescribed medications, including opioids, without consulting a qualified healthcare professional.

Frequently Asked Questions

Can medical cannabis cure endometriosis?

No. Current evidence does not show that cannabis cures endometriosis. Research suggests that cannabis-based medicines may help some patients manage pain and related symptoms.

Did cannabis reduce opioid use in the study?

Yes. Average prescribed opioid burden declined over 24 months, and more than one-quarter of participants achieved a clinically significant reduction. Because this was observational research, it does not prove cannabis directly caused the reduction.

How long did the reported improvements last?

Improvements in pain, quality of life, sleep, and anxiety remained evident through the study’s 24-month follow-up.

Was the treatment free of side effects?

No. Reported effects included fatigue, lethargy, and headache, although the researchers characterized the overall adverse-event profile as favorable.

Should someone stop taking opioids and use cannabis instead?

No one should abruptly stop prescribed opioids or substitute cannabis without medical supervision. Treatment changes should be planned with a qualified healthcare professional.

Sources

• National NORML: Study—Endometriosis Patients Experience Sustained Improvements from Medical Cannabis, Reduce Their Opioid Use

• Ahmed et al.: Cannabis-Based Medicinal Products for Endometriosis—A 2-Year Prospective Analysis From the UK Medical Cannabis Registry