Cannabis Users May Use Less Pain Medication 2023

It is well known that people with chronic pain often use cannabis to help relieve pain and related symptoms. However, data on the extent to which people with chronic pain have replaced medications with cannabis are limited, wrote Mark C. Bicket, MD, PhD, of the University of Michigan, Ann Arbor, and colleagues, in a recent review.

To help address the lack of research, the FDA announced the development of a new regulatory pathway to ensure that cannabidiol products meet safety standards in a statement issued on January 26, 2023. The agency plans to continue monitoring the marketplace, identify cannabis products that pose risks, and take action “within our authorities” if needed, according to the statement.

In the meantime, Dr. Bicket and colleagues conducted a survey to get more detail.

Cannabis Use Study in People with Chronic Pain

Methods

Bicket and team surveyed 1,724 adults aged 18 years and older with chronic pain from the 36 states with active medical marijuana programs, plus Washington, D.C. Of these, 1,661 completed the full survey. Participants were identified using the National Opinion Research Center AmeriSpeak panel and invited to complete a survey between March 3, 2022, and April 11, 2022. Chronic noncancer pain was defined as pain unrelated to cancer on most days or every day in the past 6 months. The mean age of the participants was 52.3 years, and 57% were female.

Findings

Overall, 31% of the participants reported ever using cannabis for pain management. Of these, 25.9% reported using cannabis for pain in the past 12 months, and 23.2% reported use of cannabis for pain in the past 30 days.

A majority of the medical cannabis users (94.7%) also reported using at least one other pharmacologic treatment for pain, and 70.6% reported using at least one other nonpharmacologic treatment.

More than half of adults who used cannabis for chronic pain reported reducing their use of prescription and nonprescription pain medications over a 12-month period, including prescription opioids, prescription nonopioids, and over-the-counter pain relievers. Less than 1% of cannabis users reported that cannabis use increased their use of other medications.

Additionally, 38.7% of medical cannabis users said that cannabis use decreased their use of physical therapy to manage pain, 19.1% reported a decreased use of meditation, and 26.0% reported a decreased use of cognitive behavioral therapy. A total of 5.9%, 23.7%, and 17.1% reported that cannabis use increased their use of physical therapy, meditation, and cognitive behavioral therapy, respectively.

“The high degree of substitution of cannabis with both opioid and nonopioid treatment emphasizes the importance of research to clarify the effectiveness and potential adverse consequences of cannabis for chronic pain,” wrote Bicket et al.

They noted that their study was limited by the use of self-reports, the potential for sampling biases, and a lack of data on possible changes in pain treatment because of factors such as forced opioid tapering, the authors noted.

However, the findings suggest that state cannabis laws have improved access to medical cannabis as a treatment for chronic pain despite the limited evidence for its use as a substitute for other pain treatments, they said.

Overall, Bicket’s review adds to the knowledge of the proportion of the general population using cannabis or marijuana for any purpose, said E. Alfonso Romero-Sandoval, MD, PhD.

“In the US, approximately 15% of adults have used marijuana or cannabis in the last year, which is three times more than 20 years ago, encompassing the increase in the legal availability of marijuana across the country,” said Dr. Romero-Sandoval, an associate professor of anesthesiology and social sciences and health policy at Wake Forest University, Winston-Salem, NC.

“Once you have a population suffering a debilitating condition for which there is no effective treatment, you would expect these patients to seek alternative treatments that modern medicine or modern pharmacy cannot provide,” said Dr. Romero-Sandoval. “There is evidence that cannabis could moderately treat chronic neuropathic pain, though not reduce it completely, in some portion of pain patients,” he said.

“However, the procedures followed in the US to make cannabis-based medicines available to patients in a safe and controlled manner have failed, while other countries have progressed more efficiently,” he said. Therefore, the high prevalence of medical cannabis use is not surprising, but it is worrisome, he added. “The lack of progress in the field leaves a void filled by other entities that might not provide a safe environment for patients.”

The key message to clinicians is to learn the pharmacology of cannabinoids since many of their pain patients have tried or will try them, said Dr. Romero-Sandoval.

Many individuals with chronic pain “have minimal options to manage their pain; therefore, they are at risk of using non-regulated products and might be using them already,” he emphasized. “Know what effects are produced with different doses or concentrations, just as with any other drug,” he said.

“Provide guidance and advice, talk about the irregularities of the market and products, and discuss potential benefits and realistic likely adverse events,” said Dr. Romero-Sandoval. “Establish an open, candid dialogue about the uncertainties of the status of medical cannabis, but do not judge; instead, listen, and be ready for a difficult conversation that medical school did not prepare you to have,” he said.

So Much More to Learn

Looking ahead, “We need longitudinal randomized controlled trials with different types of products and cannabinoids,” Dr. Romero-Sandoval noted. “But we also need to understand the attitudes and perceptions of the general public and pain patients about cannabis, including their source of information, why they believe that currently available marijuana, which is very potent and primarily designed for recreational purposes, is safe and effective.”

“The evidence shows that self-reported outcomes are favorable to marijuana. Still, when these outcomes are compared to a placebo in well-controlled trials, the benefits are not different from a placebo,” Dr. Romero-Sandoval added.

More research is needed to show which benefits associated with cannabis are superior to a placebo effect or the effects of existing medications and whether those benefits outweigh the risk of cannabis use or the risks of commonly used analgesics, Dr. Romero-Sandoval said.

For example, “We know that inhaled and oral administration produces differential effects because cannabinoids are processed differently by the body; we need to know what route of administration is more effective, more convenient, and safer and at what doses or concentrations we could see desirable and adverse effects.”

The Bicket et al study was supported by the National Institute on Drug Abuse (NIDA). Dr. Bicket disclosed grants from the National Institutes of Health, the Centers for Disease Control and Prevention, the Michigan Department of Health and Human Services, the Arnold Foundation, and personal fees from Axial Healthcare, as well as grants from the Patient-Centered Outcomes Research Institute outside the current study. Dr. Romero-Sandoval had no financial conflicts to disclose.