Decoding Cannabis: Is medical cannabis effective for period pain?

Queen Victoria just may have been onto something all those years ago. 

Not just one of the most recognisable figures in British history, but one of the first high-profile cases of someone rumoured to be taking medical cannabis for period pain. It's said her physician, Sir J. Russell Reynolds, prescribed cannabis tincture for her period pain, and later wrote: “When pure and administered carefully, [cannabis] is one of the most valuable medicines we possess.” 

Welcome back to Decoding Cannabis. Every week, we take one of the more recent pieces of medical cannabis research and break it down into something a little more clear and accessible. 

Whether you’re a patient, clinician, or just curious, the goal is to move past the hype and focus on what the evidence actually shows. 

In today's edition, we’re looking at a 2022 review titled “Dysmenorrhoea: Can Medicinal Cannabis Bring New Hope for a Collective Group of Women Suffering in Pain, Globally?”

This is not a systematic review, but instead a narrative review. That means it doesn’t give a strict study count or selection process. Instead, it draws from a range of papers (around 17 key sources) covering everything from cannabinoid mechanisms to patient surveys and early clinical research on medical cannabis for menstrual cramps.

Medical cannabis is now legally prescribed for period pain in the UK

For many people assigned female at birth in the UK, the fact that medical cannabis for period pain can be legally accessed is still a pretty novel idea, and one that usually only comes into the picture after other prescribed treatments fail. But it is a fully legal treatment option, and has been since November 2018. 

Want to learn more? Head to fast and free medical cannabis eligibility checker - it takes just 20 seconds to complete and is totally obligation free. 

What causes period pain? 

Period pain is a fickle beast. Pinning it down to one root cause isn’t always possible, but for most women, it starts in the uterus (or to be more specific, the prostaglandins contained in the uterus). Prostaglandins are hormone-like chemicals that fill a range of functions, one of which being the triggering of the uterus muscles to contract, which (from a purely biological standpoint) help shed the uterine lining each month. 

But when prostaglandin levels are too high, the contractions become more intense and painful. They can also reduce blood flow, which adds another layer of discomfort.

Primary vs secondary dysmenorrhoea, and where cannabis might fit alongside standard treatment options 

There are two main types of period pain: 

• Primary dysmenorrhoea refers to cramping without an underlying medical condition. For most women, this type of menstrual cramping starts during their first period and follows a regular monthly pattern until menopause set in. 
• Secondary dysmenorrhoea is the team used to describe menstrual cramping that is exacerbated by another health condition, such as endometriosis, fibromyalgia, or general pelvic inflammation. This pain is sometimes described as more intense, more localised, longer-lasting, and (in many cases) harder to treat.

Inflammation is common in both types of period pain, as is heightened nerve sensitivity. That’s one of the main reasons why treating dysmenorrhoea usually involves more than just quieting those uterus contractions, it’s about addressing the wider pain response too.

The paper in question focuses on primary dysmenorrhoea, as will we for the rest of this blog.

What does the research say about cannabis for menstrual cramps?

As we started this blog off with, cannabis for menstrual cramps isn’t a new idea, but that doesn't mean that there is an abundance of clinical evidence to pull from. Unfortunately, at the time of this review being published, there were simply no large-scale randomised controlled trials focused solely on menstrual pain. 

There are when it comes to medical cannabis for pain more generally, but as is the way with most women specific health issues, the science has been slower to play catch up when it comes to gold-standard research into medical cannabis for period cramps. 

We hope to see more data released in the coming years, and when it does, we will report on it. 

What we do have in this narrative review is a compilation of observational reports, patient experiences, and broader clinical findings that start to fill in the gaps. While no randomised controlled trials have yet been peer-reviewed, the authors highlight real-world data showing how patients are already using cannabis for cramps, especially when conventional treatments fail or cause unwanted side effects.

Many of the reports included in the review describe women turning to cannabis not as a first-line option, but as a practical response to unmanaged pain. And here in the UK, that makes sense. While medical cannabis for women’s health issues is a legal treatment option, patients must first try at least two conventional treatment options before they can be considered for cannabis-based treatment options. 

Medical cannabis flower (administered through a dry herb vaporiser) and THC vapes offer almost instant symptom control (depending on the condition being treated), while medical cannabis oil options (either THC dominant, CBD dominant, or balanced) have a slower onset with longer-lasting effects. 

How cannabis compounds like THC and CBD might help with period pain

The authors of the 2022 review in question collated insights from not just pain research papers, but also cannabinoid pharmacology research and patient-reported outcomes to piece together a biological explanation that makes a lot of sense. 

The two major cannabinoids produced by the Cannabis sativa L. genus (THC and CBD) have been proven to interact with the body’s endocannabinoid system (ECS). The ECS plays a significant role in regulating pain, mood, inflammation, and muscle function. 

The authors of the paper steer clear of making any bold or definitive claims. But they present a strong case for why cannabis might work, based on what we already know about how it behaves in the body.

Learn more: Decoding Cannabis: What real patients say about cannabis for chronic pain

Can THC help with period pain?

Tetrahydrocannabinol (THC) is the cannabinoid that produces the intoxicating, sometimes described as euphoric, effects of cannabis, but it’s also one of the most widely studied when it comes to pain (among a wide range of other therapeutic applications. 

In this review, the authors highlight THC as one of the core therapeutic compounds under consideration for dysmenorrhoea. They reference broader the clinical findings around THC’s ability to dull how we perceive pain, and how we respond to it. 

• THC acts as a partial agonist at both CB1 and CB2 receptors (it binds more easily to the CB1 receptor sites, but sill interacts with CB2 receptors). 
• CB1 receptors are mostly located in the brain and central nervous system and, when activated, modulate our response to pain, our mood, and even our overall perception (which explains the intoxicating effects of THC). 
• CB2 receptors are found more peripherally and are particularly relevant to chronic inflammatory pain, which can be part of the picture in secondary dysmenorrhoea. 

What makes this particularly fascinating in the context of period pain is that three key cannabis-relevant receptors that influence pain perception (CB1, CB2, and TRPV) have been found in the muscular outer layer of the uterus that is responsible for the cramp inducing contractions. 

The review points to early research suggesting that cannabinoid activation, particularly at CB1, may relax these muscles and reduce painful contractions. That may help explain why so many people with conditions like endometriosis or treatment-resistant cramping report meaningful improvements when using cannabis-based products. 

The paper also notes that many patients with gynaecological pain (including chronic pelvic pain and vulvodynia) already use CBPMs (cannabis-based products for medicinal use), often reporting improved pain scores. 

Can CBD help with menstrual cramps?

Cannabidiol (CBD) does not offer up any euphoric effects like THC, but it’s far from inactive, and is still counted as “psychoactive” thanks to its ability to shift mood but not perception.

Rather than binding directly to cannabinoid receptors like THC, it appears to act as a modulator, influencing the endocannabinoid system in more indirect ways. It has been shown to reduce the enzymatic breakdown of one of our naturally produced cannabinoids, anandamide, which plays a key role in regulating mood and pain. By helping anandamide stick around longer in the body, CBD may support a more stable internal environment and reduce the sensitivity to pain signals.

This mechanism, combined with its activity at TRPV1 receptors found in the uterus, offers a compelling explanation for why some people find relief from menstrual cramps when using CBD. The review highlights this as a biologically plausible pathway. One that could help explain the muscle-relaxing and anti-inflammatory effects reported by patients, even though clinical trials focused specifically on period pain are still lacking.

There’s also some evidence pointing to its ability to reduce anxiety and improve sleep, two things that often get worse during painful periods.

This research, combined with the real-world reports from patients already taking medical cannabis treatment options for period pain, show that more research is needed so we have more concrete results. That said, it’s clear that this is an area worth watching.

Is medical cannabis a real option for chronic period pain relief?

The evidence is still early, but it’s more than promising. The review we’ve decoded doesn’t claim cannabis is a silver bullet, and it doesn’t need to. What it does is offer a grounded, biologically plausible rationale for why medical cannabis might help with period pain, especially when standard treatments haven’t worked or aren’t well tolerated.

Sound like something you’re currently dealing with?

Jump over to our medical cannabis eligibility checker and see if medical cannabis may be a potentially life-changing treatment option for yourself. 

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