Can Cannabis Help Endometriosis Patients?

Overview

Cannabis can provide significant relief for endometriosis, by modulating and activating the endocannabinoid system — a key system which affects this condition. 

While some treatments and surgeries exist to treat this condition, they are not always effective at alleviating the often intense pain that comes with endometriosis, so more options are desperately needed for the women who are suffering from this challenging and painful condition. Cannabis is one potential therapy currently being researched. 

How Cannabis Works on Endometriosis 

To get a good idea of how cannabis might be able to help with endometriosis, we first need to understand how endometriosis is affected by the endocannabinoid system. This crucial system in the human body is made up of endocannabinoid receptors (called CB1 and CB2), endocannabinoids (natural chemicals in the human body which activate or modulate CB1 and CB2 activity), and enzymes which metabolize the endocannabinoids and clear them from the body. This system is tasked with maintaining homeostasis — and keeps many of our most important functions in balance. Modulating functions like sleep, hunger, pain, anxiety, nausea and energy metabolism, the endocannabinoid is a vital system for maintaining our ongoing health. 

While this system is usually activated by our own internal endocannabinoids, they can also be stimulated by chemicals in cannabis called cannabinoids. These chemicals work similarly to our natural endocannabinoids.

As it turns out, the endocannabinoid system is also involved in endometriosis and its associated pain. Researchers had suspected this might be the case because women reported reduced pain when using cannabis for their endometriosis. Specifically, scientists hypothesized that the endocannabinoid system was involved in both the development of endometriosis, and in the manifestation of its associated pain. The found several pieces of evidence to support their theory. 

For one thing, studies have recently found that sensory and sympathetic nerve fibers actually sprout branches into these abnormal tissue growths, innervating them with sensation and allowing them to feel pain. These fibers are rich with CB1 receptors, and thus can be modulated with endocannabinoids or the cannabinoids in cannabis (which can both activate CB1). Not only are the fibers and growths rich in CB1, but so are the neurons from which these fibers sprout. 

Researchers explain that all of this could suggest that the endocannabinoid system plays an important role in the progression of endometriosis and the sprouting of innervating fibers. 

We can also see in fertility research that higher levels of anandamide (a CB1 stimulating endocannabinoid) at ovulation and lower levels at implantation is important for a successful pregnancy. Alterations in these endocannabinoid signaling can even lead to miscarriage, so we know that the endocannabinoid system plays an important role in the female reproductive system.  

There is also a significant increase in endocannabinoid levels, along with decreased levels of CB1 receptors, in women with endometriosis compared to those without endometriosis. This result suggests a negative feedback loop in pain regulation, which may impair the capability of the endocannabinoid system to control pain in endometriosis patients. 

All of this evidence has even led some researchers to describe endometriosis as an “endocannabinoid deficiency” condition.

Medical Studies on Cannabis and Endometriosis

So it’s clear that the endocannabinoid system plays an important role in endometriosis, but does that mean that cannabis can help treat it? To find out, we need to look at the research on cannabis as a treatment for endometriosis in human subjects.  

Of course, using cannabis to treat gynecological problems is nothing new. Cannabis actually has an ancient tradition of being used as a medicine in obstetrics and gynecology. It’s been used historically to treat conditions like dysmenorrhea, dysuria, hyperemesis gravidarum, and menopausal symptoms. And to this day, many women report positive effects from using cannabis for endometriosis pain. 

Still, there are very few studies (and no clinical studies) which actually research the impact of cannabis on endometriosis in humans. But we do have two recent survey based studies which asked women suffering from endometriosis how cannabis worked for them. 

The first study looked at women with endometriosis aged 18 to 45, who live in Australia. They asked about what types of self-management methods the subjects used to work with their endometriosis symptoms, along with questions about changes in symptoms or medication use, costs, and adverse events. Seventy-six percent of respondents reported using self-management techniques, and 13% of those subjects said they used cannabis. Those who did use cannabis reported high levels of pain reduction (7.6 of 10), with 56% also reporting that they were able to reduce pharmaceutical medications by at least half. These women reported the greatest improvements in sleep, nausea and vomiting, and adverse effects were relatively rare (10%) and minor. 

The authors of this study argue that these results warrant follow-up with more clinical studies to confirm cannabis’ potential to treat endometriosis. 

In another 2019 survey, patients responded to questions about their experience with cannabis and CBD (another cannabinoid) for the management of endometriosis and pelvic pain. The majority reported that it was moderately or very effective. 

Endometriosis and CBD

In the same 2019 survey where cannabis was reported to be very or moderately effective in 75.9% of cases, researchers also asked about CBD. Around a third of respondents reported having tried CBD, with more than half of these reporting CBD to be very or moderately effective. 

Among both of the participant groups, cannabis was most likely to be reported as very effective, while CBD was most likely to be reported as moderately effective.

This study gives more evidence of cannabis’ helpful role for endometriosis, and shows that it is a common treatment being used. It also sheds light on the relative efficacy between CBD and whole plant cannabis — suggesting that cannabis might be more effective that CBD alone. 

Potential side effects of cannabis use

While there hasn’t been much clinical research on using cannabis for endometriosis, in the studies we do have, adverse effects were relatively rare (affecting around 10% of patients) and were generally minor. In general, side effects from cannabis are modest but can include symptoms like mild difficulties in concentration and memory,  impaired coordination, increased appetite, nausea, racing heart, light-headedness, dry mouth, and fatigue. 

In addition, cannabis may interact with some drugs in a harmful way — slowing their metabolism and consequently increasing the amount of the drug present in the bloodstream. This could lead to overdose issues with certain medications. Those taking other medications should always consult with a doctor before beginning cannabis use to ensure there are no conflicts with pre-existing medications.