CBD Effectiveness in Treating Chronic Pain Remains Questionable

Jennifer Middleton, MD, MPH
Posted on April 8, 2024

Last year, the U.S. Substance Abuse and Mental Health Services Administration published survey data showing that approximately 1 in 3 U.S. adults have used cannabidiol (CBD) products as of 2020. Although derived from the same plant as marijuana, CBD contains very small  quantities of tetrahydrocannabinol (THC), the compound responsible for marijuana’s psychoactive effects. Many patients use CBD products hoping for relief from chronic pain, but a recently published study shows only minimal, if any, benefit for this indication.

The study is an update of a 2021 systematic review that included 36 randomized control trials (RCTs), all with high or uncertain risk of bias. The 2021 systematic review did not find any benefit from CBD, cannabis, and cannabis-based medicines for chronic pain, although the authors acknowledged that “outcomes had GRADE rating of low- or very low-quality evidence.” The 2024 update looked at 16 RCTs that had been published since 2021 with varied types of CBD products, including oral, topical, and buccal/sublingual formulations with doses ranging from “6 and 1,600 mg and durations of treatment between a single dose and 12 weeks.” No significant difference in perceived pain between CBD and placebo was found in the 15 RCTs; the trial that did show a positive benefit to CBD had only 18 participants. The authors also discuss the growing recognition of CBD’s potential effect on worsening liver function and increasing rates of cannabis use disorder.

An Agency for Healthcare Research and Quality (AHRQ) systematic review was consistent with these findings (discussed in a 2022 AFP AHRQ review); these authors found only a small clinical improvement with CBD use compared with significant reported adverse effects. A 2022 BMJ Rapid Review found that “[n]on-inhaled medical cannabis or cannabinoids slightly improve pain levels, with a number needed to treat of 10 (95% CI, 7 to 20) to decrease average pain by 1 cm more on a 10-cm visual analog scale compared with placebo,” but they also found that dizziness was a frequent adverse effect.

Importantly, the aforementioned studies examined the use of CBD products that had been independently verified, but the vast majority of CBD use in the United States comprises over-the-counter (OTC) CBD products. The composition of OTC CBD products is not always verified, and patients wanting to purchase OTC CBD should “make sure that there is independent laboratory testing as attested to by a COA (certificate of analysis) that should accompany every CBD product.” Unfortunately, these “[OTC] CBD products are often advertised as therapies for many health conditions, even though many of these claims are unproven and the health effects of these products are unknown.” OTC CBD is a multibillion dollar business, and patients choosing these products to treat chronic pain should be aware that companies can and do make unsubstantiated promises about the effectiveness of their products.

Chronic pain adversely affects patients’ quality of life, and current pharmaceutical treatment options for it remain limited. Acetaminophen is ineffective for arthritis, nonsteroidal anti-inflammatory drugs carry significant risk of adverse effects, and opioid medications have fueled a worldwide addiction epidemic. We can validate the frustration of our patients who have chronic pain as we share the evidence available to date regarding CBD’s effectiveness. Read more in AFP By Topic: Chronic Pain and find additional resources in the AAFP Chronic Pain Management Toolkit.