Clinical Trial Finds High-Dose CBD Reduces Neuropathic Pain in Spinal Cord Injury Patients
- A placebo-controlled clinical trial found that high-dose oral cannabidiol (CBD) significantly reduced chronic neuropathic pain in adults with spinal cord injuries, with pain scores averaging 3.82 during CBD treatment versus 4.36 with placebo.
- The randomized, double-blind, crossover study involved 40 adults, who received up to 800 milligrams of CBD daily over six weeks, showing that 37.8% achieved at least a 30% reduction in pain compared to 11.1% on placebo.
- Adverse events were common but mostly minor and similar between CBD and placebo groups, including tiredness, nausea, diarrhea, and stomach discomfort.
- Researchers concluded that while the pain reduction was modest, the findings support further investigation of high-dose CBD as a potential treatment for chronic neuropathic pain in spinal cord injury patients, noting the limited relief from current therapies.
(Photo credit: Mayo Clinic).
A new placebo-controlled clinical trial found that high-dose cannabidiol (CBD) significantly reduced chronic neuropathic pain in adults with spinal cord injuries, with researchers saying the findings support further study in larger trials.
The study, published by eClinicalMedicine, was conducted by researchers from the University of Sydney and the University of New South Wales. It examined whether oral CBD, taken at doses up to 800 milligrams per day, could reduce chronic neuropathic pain related to spinal cord injury.
The randomized, double-blind, placebo-controlled crossover trial was conducted at Neuroscience Research Australia. Forty adults with spinal cord injuries and neuropathic pain lasting at least three months were randomized, with 38 included in the primary analysis. Participants received CBD and placebo during two separate six-week treatment periods, divided by a four-week washout period.
CBD was gradually increased over two weeks, starting at 200 milligrams per day before reaching 800 milligrams per day. Participants reported pain intensity using a zero-to-10 Visual Analogue Scale three times daily on alternate weekdays.
Researchers found that pain intensity was significantly lower during the active CBD phase compared to placebo. Pain scores averaged 3.82 during CBD treatment, compared with 4.36 during placebo, a difference researchers described as statistically significant but modest.
The study also found that 37.8% of participants receiving CBD achieved at least a 30% reduction in pain, compared with 11.1% during placebo treatment. On average, pain fell 14% during the final week of CBD treatment, compared with 6.5% with placebo.
Adverse events were common in both groups but were generally minor. During CBD treatment, 68.4% of participants reported adverse events, compared with 52.6% during placebo. The most common events during CBD treatment included unusual tiredness or sleepiness, nausea, diarrhea, feeling unwell, loss of appetite and stomach discomfort. Researchers said the overall adverse event rate was similar between CBD and placebo.
“While modest in magnitude, the observed effect supports further research into high-dose CBD for chronic neuropathic pain,” researchers wrote.
They noted that chronic neuropathic pain affects more than two-thirds of people with spinal cord injuries and that current treatments often provide limited relief while carrying significant side effects. Researchers said the trial adds early clinical evidence that higher-dose CBD may benefit some patients, particularly after previous CBD pain trials using much lower doses failed to show significant effects.
The study was funded by Spinal Cord Injury Research Grant NSW Health and the Lambert Initiative for Cannabinoid Therapeutics at the University of Sydney.