Cannabis for Pain Relief: An Area Ripe for Research

Editor’s note: ACR on Air, the official podcast of the ACR, dives into topics important to the rheumatology community, such as the latest research, solutions for practice management issues, legislative policies, patient care and more. Twice a month, host Jonathan Hausmann, MD, a pediatric and adult rheumatologist in Boston, interviews healthcare professionals and clinicians on the rheumatology front lines. In a series for The Rheumatologist, we provide highlights from these relevant conversations. Listen to the podcast online at acronair.org, or download and subscribe to ACR on Air wherever you get your podcasts. Here we highlight episode 29, Cannabis as Pain Management, which aired on May 24, 2022.

In states or countries where it’s legal, medical cannabis may be an effective option for pain management for patients with rheumatic disease. For patients interested in this option, rheumatologists should provide guidance on purchasing medical cannabis from licensed providers and steer specific patient groups, such as younger or older patients, away from its use, says Mary Ann Fitzcharles, MD, associate professor of medicine in the Division of Rheumatology and the Allen Edwards Pain Management Unit, McGill University, Montreal.

Dr. Fitzcharles

Dr. Fitzcharles helped develop the Canadian Rheumatology Association physician statement on medical cannabis and is the co-chair of the ACR Pain & Fibromyalgia Abstract Committee. She spoke with Dr. Hausmann, ACR on Air podcast host and a pediatric and adult rheumatologist in Boston, about the use of cannabis for pain management.

Cannabis Evolution

Although cannabinoids have been used in medicine for more than 5,000 years, its legal status has hindered the ability to conduct research with it, Dr. Fitzcharles says.

Access to cannabis for patients and research began to relax with the legalization of medical cannabis in California in 1996 and in Canada in 2001. However, in the beginning, access was still limited. That access has changed now that medical cannabis is legal not just in Canada, but also in 38 U.S. states and the District of Columbia. Recreational cannabis is also legal in 22 U.S. states, the District of Columbia and Canada.¹

Dr. Hausmann recalls being in medical school in the early 2000s and learning that pain should be aggressively treated with opioids. Cannabis was looked at negatively.

“Fast forward 15 years, and it seems like it’s the complete opposite,” he says. “Opioids are now looked at with a negative light, and cannabis is having a resurgence of interest and applications.”

Cannabis for Medical Use

Cannabis has an herbal form and a medical formulation. The medical formulation is a regulated pharmaceutical product with established good manufacturing practices, as well as set dosages, indications and contraindications. The majority of cannabis studies focus on pharmaceutical products rather than herbal cannabis. This distinction makes it hard to collectively understand the effects of herbal cannabis.

“Our patients are using the herbal product, and we truly don’t know the ideal dosing. We don’t know the ideal combination. We don’t know the ideal strain,” Dr. Fitzcharles says.

She notes that physicians focusing on cannabis for their patients should use the term medical cannabis instead of marijuana, which has recreational connotations.

Cannabinoids work on the body’s endocannabinoid system, which helps regulate several functions in the body, including pain. The two most studied molecules in cannabis are tetrahydrocannabinol (THC) and cannabidiol (CBD). However, other molecules mixed with the plant contribute to its potential benefits for pain or other medical conditions. The way the plant is grown may also affect its utility, such as where it was grown, lighting and more.

Pain Perception & Rheumatology

With her dual background in rheumatology and pain management, Dr. Fitzcharles became involved in researching cannabis as it became more accessible in Canada. Her studies have found that pain sometimes endures in rheumatological disease even under good circumstances.

“We know that even with beautiful control, many patients still have a remaining pain or secondary fibromyalgia, or what we now call a component of nociplastic pain,” she says.

Nociplastic pain may be out of proportion to perceived tissue damage and does not respond to traditional treatments, such as opioids and anti-inflammatory drugs. These concerns are why physicians are researching other treatments, such as anti-epileptic therapies, some forms of anti-depressants and cannabinoids.

One challenge with cannabis is the lack of a large body of research, such as randomized controlled trials and systematic reviews, that other traditional treatments have to support its use, Dr. Fitzcharles notes. More research exists on medical formulations and very little on herbal cannabis, particularly for rheumatology.

“There have been [fewer] than 200 rheumatology patients studied in [randomized controlled trials] looking at the effects of pharmaceutical cannabinoids. There have been 58 patients with rheumatoid arthritis and a handful of patients with fibromyalgia and a few patients with low back pain,” Dr. Fitzcharles says.

This lack of data makes it harder to truly understand the effectiveness of herbal cannabis beyond cohort studies, dispensary-sponsored studies and patient self-reporting.

The lack of research on medical cannabis for rheumatic disease or chronic pain syndromes makes this an area for potential exploration with a Rheumatology Research Foundation grant or U.S. National Institutes of Health grant, Dr. Hausmann says.

However, it’s clear the use of medical cannabis has increased with more legalization. Dr. Fitzcharles was part of two studies in Montreal that surveyed 1,000 patients with rheumatic disease before and after recreational legalization. Researchers found the use of medical cannabis doubled after legalization, from 15 to 30%.²

“Patients are now trying it themselves, so not necessarily coming through the medical stream because they can just go and buy it legally,” she says.

The demographics of patients trying medical cannabis have also changed. Ten years ago, younger patients were more likely to use cannabis recreationally, Dr. Fitzcharles says. Now, more women and patients over the age of 60 are using cannabis, particularly oral vs. smoke-based products.

Dr. Hausmann notes that patients may be seeking out medical cannabis because rheumatologists are not doing enough to help patients manage their pain. But it’s encouraging that these patients now have more options for pain management.

The majority of studies focus on pharmaceutical products vs. herbal cannabis, which makes it hard to collectively understand the effects of the herbal form of cannabis.

Pearls for Pain Management & Cannabis

Dr. Fitzcharles shared some pearls to help rheumatologists guide their patients on medical cannabis use.

1. Remember that medical cannabis is not for everyone.

The position statement from the Canadian Rheumatology Association on medical cannabis for outpatients has guidance on patients who should avoid medical cannabis.³ They include:

• Patients under the age of 25 because their brains are still developing;
• Pregnant patients because cannabinoids can cross the placenta and harm the fetus;
• Patients who are breastfeeding;
• Patients over the age of 60 because they are more likely to use multiple medications, which can increase the risk of drug interactions, and the use of cannabis may increase their risk of falling;
• Patients with mental health conditions; and
• Patients with moderate to severe cardiovascular or pulmonary disease.

Dr. Fitzcharles also discussed the dangers of driving while actively using cannabis, which can slow a person’s judgment.

2. Advise patients to focus on oral preparations rather than inhaled forms of medical cannabis.

This type of cannabis may help patients avoid the adverse effects of smoking on rheumatic disease.

3. Encourage patients to start with a low dose as a capsule or oil.

A cannabis product with a very low level of THC and more CBD, up to 2.5 mg, is ideal. This cautiousness can help avoid injuries, such as falls, Dr. Fitzcharles says.

“Start with a tiny dose at nighttime, and see how [the patient] feels, but with the knowledge that even a tiny amount of THC can cause psychomotor effects,” she says.

4. Encourage patients to understand what they’re purchasing and to get it from licensed provider or dispensary.

This approach makes it easier for patients to get a product without unpredictable THC levels or contaminants.

Dr. Fitzcharles says she also emphasizes good lifestyle choices for better pain management, such as a balanced diet, a healthy weight, more physical activity and adequate sleep, with her patients.

References

1. State medical cannabis laws. National Conference of State Legislatures. 2023.
2. Fitzcharles MA, Rampakakis E, Sampalis JS, et al. Use of medical cannabis by patients with fibromyalgia in Canada after cannabis legalization: A cross-sectional study. Clin Exp Rheumatol. 2021 May–Jun;39 suppl 130(3):115–119.
3. Fitzcharles M A, Niaki OZ, Hauser W, et al. Position statement: A pragmatic approach for medical cannabis and patients with rheumatic diseases. J Rheumatol. 2019 May;46(5):532–538.

More Episodes

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