Study Does Not Find Sufficient Evidence of Medicinal Cannabis Use for Chronic Pain

Medicinal cannabis has become increasingly accepted in the United States and is commonly used for pain management. Despite its growing popularity as a treatment, there is little evidence available about the harms and benefits of cannabis utilization.

A study recently published in Annals of Internal Medicine evaluated the benefits and potential harm of plant-based cannabis used for treating chronic pain in the general adult population. The researchers collected data from previous cannabis studies that reported on pain, quality of life, or adverse effect outcomes. Additionally, neuropathic pain studies were collected and used to assess the strength of the pain relief outcomes.

A total of 27 randomized controlled trials were considered in the study for analyzing the effects of cannabis in treating chronic pain. Of the 13 trials examined for neuropathic pain, there was low strength evidence of cannabis’ ability to alleviate this pain and insufficient evidence for other pain populations.

Two trials and 3 cohort studies examined the effects of cannabis on pain among patients with pain conditions, including fibromyalgia, rheumatoid arthritis, and inflammatory abdominal pain.

“Overall, evidence was insufficient because of the inconsistent results and the paucity of methodologically rigorous studies,” the authors wrote.

Additionally, according to 11 systematic reviews and 32 primary studies, the harms involved with cannabis in the general population include a greater risk for motor vehicle accidents, psychotic symptoms, and short-term cognitive impairment. When the reviews considered the younger population, they did not find the presence of adverse pulmonary effects and did not find sufficient evidence of the physical harms of long-term cannabis users in older populations.

“Even though we did not find strong, consistent evidence of benefit, clinicians will still need to engage in evidence-based discussions with patients managing chronic pain who are using or requesting to use cannabis,” the authors concluded. “Therefore, clinicians must understand what is known and unknown about its potential harms.”

Due to the lack of sufficient evidence to make conclusions on the effects of cannabis utilization for chronic pain, there is a need for more research to establish the potential harms and benefits, especially as the recreational and medicinal use of plant-based cannabis becomes more accepted.