Considering Cannabis for Migraine Pain? Here’s What You Need to Know

From triptans to the new calcitonin gene-related peptide (CGRP) inhibitors, there are more and more evidence-based treatments for migraine, a leading cause of disability worldwide.

But migraine treatment is not a one-size-fits-all proposition, and even with the availability of newer, more targeted drugs, as many as 60 percent of people fail to find adequate or consistent relief, according to a report published by Neurology Today in 2020. 

No wonder interest in complementary herbal and plant-based therapies, including medical cannabis, is growing. 

Nancy Thompson, a 55-year-old Canadian citizen, is one of those people seeking alternatives. Thompson has had migraine attacks since she was a teenager, and once they became frequent (occurring six to seven times weekly), her general practitioner sent her to a neurologist, who prescribed a variety of treatment strategies.

“We tried a bunch of different things, including an anti-seizure medication and Botox, and for me, they just weren’t doing much of anything. The Botox we considered a success because I would go one day a week without a migraine,” she says.

Desperate for a solution, she and her husband decided, albeit reluctantly, that she should try cannabis. 

“I was very apprehensive of it. I had absolutely no idea what would happen,” Thompson says.

Cannabis Use for Headaches Is Not Uncommon

Thompson is not alone in her decision to try cannabis for what has been a lifetime of severe, debilitating headaches. In a survey of U.S. and Canadian adults published in Psychopharmacology in May 2022, as many as 35 percent reported using cannabis to treat their headaches and migraine. 

In another survey, published in the Canadian Journal of Neurological Science in September 2021, 34 percent of 200 Canadian patients attending a headache clinic reported using cannabis both for prevention and acute treatment and often at the same time.

Sixty percent reported that cannabis reduced the severity of their headaches, while about 30 percent said it prevented their headaches altogether.

Thompson also had a positive experience. With her neurologist’s blessing, a doctor’s prescription, and guidance from a licensed medical cannabis producer, she started vaping cannabis flower. Within three weeks, she went one day without any migraine symptoms, followed by two, and then by three, and then an entire week. 

When her migraine symptoms do manage to break through, she says, their duration is slightly shorter. More important, “the pain is nowhere near as bad, that’s for sure, and I can usually get away with just some Tylenol or Advil, go lie down, and within a few hours, I’ll be better,” she says.

Thompson also has prescription rescue medication (including a triptan and a buffered aspirin with caffeine) just in case she fails to find relief with cannabis alone. 

Everything Old Is New Again

The link between medical cannabis and migraine is not new. Cannabis has a long history of use in treating severe headache-like pain, with one of the earliest mentions of it dating back to the second millennium B.C. Throughout the centuries that followed, medical cannabis shifted in and out of fashion before regaining its place in modern Western medical toolboxes in the 1840s.

“From 1848 through 1948, cannabis was one of the most commonly used drugs for treatment of migraine,” says Lazlo Mechtler, MD, the medical director of the Dent Neurologic Institute, the Dent Headache Center, and the Cannabis Clinic in Buffalo, New York. 

“In the United States, William Osler (the father of modern medicine and a founding member of Johns Hopkins Medical School) used cannabis for treatment of migraines. So did William Gowers, the founding father of neurology in England,” he says.

“Unequivocally, cannabis was one of the drugs of choice back then.” 

That is, until the federal government decided to tax and criminalize cannabis in 1937, remove it from the U.S. pharmacopeia in 1942, and then classify it as a Schedule 1 substance in the 1970s (meaning that it had no acceptable medical use and was among the class of drugs having the highest potential for abuse), according to Americans for Safe Access.

Despite ongoing federal limitations, 37 U.S. states have since legalized cannabis for medical or recreational use, which has probably contributed to the renewed interest in its potential effectiveness for treating migraine and other medical conditions.

A Promising but ‘Unproven’ Treatment

Because of cannabis’s Schedule 1 status, it has been difficult for researchers to obtain special licenses and access the supply of federally endorsed cannabis for their studies.

That’s why most of the research examining cannabis in migraine treatment has been observational (meaning that outcomes are measured without introducing a specific treatment or intervention), and why many doctors have been hesitant to recommend cannabis to their patients.

These barriers notwithstanding, observational studies — especially those published within the past few years — have consistently shown benefits of medical cannabis for some people with migraine, including reduced migraine severity or monthly frequency, and have shown that cannabis can be safely substituted for ineffective pharmaceutical drugs. 

For example, findings from a study in the 2019 Journal of Pain showed that inhaled cannabis reduced the severity of migraine by almost 50 percent, regardless of the tetrahydrocannabinol (THC) or cannabidiol (CBD) content, formulation, or dose, or how severe the migraine attacks were before the participants tried cannabis.

Although many participants developed tolerance, meaning they needed higher doses over time, there did not appear to be an increase in rebound, or medication-overuse, headaches.

Cannabis use reportedly also reduced migraine frequency in as many as 60 percent of Israeli patients with migraine who participated in a questionnaire-based study. 

Findings, which were published in 2020 in the journal Brain Sciences, showed that compared with people who did not respond to cannabis, those who did experienced 50 percent fewer migraine days per month, significantly lower disability and impact scores, and better sleep quality.

When the researchers looked specifically at the chemical components of cannabis being consumed, they found that the majority — 92 percent — were THC-dominant (compared to an even ratio of THC and CBD, or CBD-dominant). In addition, use of medical cannabis tended to result in lower consumption of standard migraine medications, including opioids and triptans.

Similar findings were reported by Canadian researchers in a 2018 survey of chronic pain patients using cannabis that was published in the Journal of Headache Pain.

Roughly 45 percent of the 343 participants with probable migraine were able to replace their opioids with cannabis, while 39 percent reported similar substitutions with anti-anxiety and depression medications, and 21 percent with nonsteroidal anti-inflammatory agents (NSAIDs).

Change Is on the Horizon

Many in the medical community find themselves caught between Schedule 1 and a hard line, seeking answers that are not provided in medical school and that thus far have been lacking in the traditional evidence-based research arena. 

“Doctors have never been equipped with scientific information, prospective human data, to be able to educate patients as to what the possible benefits might be from cannabis,” says Nathaniel Schuster, MD, a pain management specialist and headache neurologist at the University of California in San Diego. 

Dr. Schuster and his colleagues are hoping to change that. 

Schuster is the lead investigator of an ongoing randomized controlled trial assessing the effectiveness of vaporized cannabis treatments in both chronic migraine (defined as more than 15 headache days per month for at least three months) and episodic migraine (defined as 14 or fewer headache days per month). 

Participants (who are still being recruited) are blindly randomized to take four puffs of vaporized flower containing THC, a THC-CBD mix, CBD, or placebo as early as possible in the course of a migraine attack. 

The primary study goal is to see whether vaping cannabis safely delivers acute headache pain relief within two hours of the treatment. The study will also evaluate whether the treatment eliminates participants’ most bothersome symptom — light sensitivity, sound sensitivity, or nausea — within two hours, as well as what effect it has on symptoms after 24 and 48 hours. 

Adding Cannabis to Your Migraine Toolbox

While the medical community eagerly awaits results of what portends to be an opening for controlled clinical research, what’s the best rule of thumb for people seeking relief now?

Before you consider trying medical cannabis for migraine, it’s important to weigh the potential risks and benefits and ideally (and most importantly) bring a doctor into the conversation. 

“Most people who have migraine have it for many years, and most people never talk to a doctor about it, so most are not using the optimal standard of care — evidence-based treatments, which are now much better than they were even a few years ago,” notes Schuster.

“Work with a doctor,” he says. “If you haven’t seen a doctor in the last couple of years, certainly see your doctor again. Migraine is a medical condition that warrants medical treatment.”

An important question to consider when choosing a doctor is whether that person has direct experience in guiding patients on how to use cannabis as migraine treatment. 

“Cannabis, or the endocannabinoid system, has not been taught in medical school for years, and only recently have physicians been exposed to that knowledge,” Dr. Mechtler says. “I started a cannabis clinic, so what I’ve done is take cannabis off the streets to a form of medical cannabis under the control of a clinician,” he adds.

Thus far, Mechtler says that he’s treated more than 13,000 patients.

Dosing and Administration

While many clinical studies have been conducted using inhaled cannabis, Mechtler does not recommend smoking, noting the risks in people with asthma or lung disease.

Instead, people with migraine who wish to try cannabis should consider vaping or tinctures, he says; either formulation quickly delivers cannabis to prevent or stop a migraine early in its tracks, since it bypasses the liver and is directly absorbed into the bloodstream.

The optimal dosing and chemical makeup (chemovars) of medical cannabis varies from person to person, so it’s wise to start low and go slow. Simply, most cannabis formulations contain one of three combinations: chemovar type 1 (THC-dominant), chemovar type 2 (combined THC and CBD), or chemovar type 2 (CBD-dominant).

While a majority of observational studies have focused on the THC-dominant approach, the decision is a personal one and should be made with a doctor’s guidance. 

“Some people respond to a one-to-one ratio, some people to THC and some people just CBD,” Mechtler says. “But you have to consider age, other medical conditions, type of migraine, frequency, and severity.” 

The trial-and-error approach also involves trying a chemovar for a period of time, then returning to the doctor for follow-up, ideally every three months for at least the first year of use.

Any discussion should include whether or not medical cannabis is helping to relieve pain, a report of side effects, the frequency and timing of cannabis use, and current dosage (including the need for higher doses to achieve the same effect). This way, the physician can adjust based on individual outcomes, and in particular, be on the lookout for potential side effects.

Side Effects to Watch For

Overall, most people appear to tolerate cannabis well, but there are a few red flags, according to a review appearing in the May 2019 Clinical Therapeutics and Pharmacology.

Although the list is hardly exhaustive, medical cannabis users should be aware of the risk for possible euphoria (“high,” especially with cannabis that is THC-dominant, and often seen in older users who’ve never tried cannabis), anxiety or paranoia, impaired cognition and driving, an increase in cardiovascular activity (including elevated heart rate or blood pressure), eventual tolerance (leading to the need for increasingly higher doses), and medication overuse headache.

Thompson says that since she started using medical cannabis, she has experienced occasional memory lapses (for example, searching for a word while speaking) but that overall, it’s been a life-changer. 

“The difference in my life is so incredible. My kids have their mom back. My husband has his wife back. I’m back in the world, able to work and do things again.”

Keep Your Options Open

For Thompson, cannabis has been a gateway toward getting her life back on track. But success varies from one person with migraine to another, which is why Mechtler considers it to be just one part of the migraine toolbox.

“I strongly believe that you don’t give patients one option,” he says, “but you have multiple different tools — one for acute migraine, one for nausea, and one could be a cannabis product. That gives power back to the patient.”