A systematic review of 21 studies found no strong evidence for cannabis being able to soothe neuropathic pain. The corresponding study was published in the Cochrane Database of Systematic Reviews.
Between 6% and 10% of the population is estimated to have chronic pain with neuropathic components. While treatments exist, they have limited efficacy. Meanwhile, cannabis has been increasingly promoted in the media as a potential treatment for the condition.
In the current study, researchers set out to assess the efficacy of cannabidiol (CBD) and tetrahydrocannabinol (THC)- containing medicines for treating chronic neuropathic pain in adults.
To do so, they analyzed 21 studies involving close to 2,200 participants with neuropathic pain. Studies were between two and 26 weeks in duration, with participants’ average age ranging from 34 to 61 years old. Research was conducted in Asia, Europe, and North America. Participants received THC-dominant medicines, balanced THC and CBD medicines, or CBD-dominant medicines. Twenty studies compared cannabis-based medicines with a placebo, while one study’s comparator was dihydrocodeine.
Ultimately, the researchers found no high-quality evidence of cannabis-based medications reducing neuropathic pain more than a placebo. The benefits and harms of cannabis-based medicines, therefore, remain unclear, wrote the researchers in their study.
When discussing limitations to their findings, the researchers wrote that the studies analyzed in their review were of ‘low’ to ‘very low’ quality. They wrote that future research could produce results that differ from those in their review.
"We need larger, well-designed studies with a treatment duration of at least 12 weeks that include people with comorbid physical illnesses and mental health conditions to fully understand the benefits and harms of cannabis-based medicines," said lead author of the study, Winfried Häuser, of Technische Universität München, Germany, in a press release.
"At present, the quality of most of the trials is too poor to draw firm conclusions,” he concluded.
Sources: Science Daily, Cochrane Database of Systematic Reviews
