(HealthDay News) — A small trial shows a dose-dependent reduction in peripheral neuropathic pain in patients with diabetes, according to a study published in The Journal of Pain.
Mark S. Wallace, M.D., from the University of California in San Diego, and colleagues conducted a randomized trial in 16 patients with painful diabetic peripheral neuropathy. They examined the short-term efficacy and tolerability of inhaled cannabis; each participant was exposed to 4 single dosing sessions of placebo or to low, medium, or high doses of cannabis in a crossover design. The authors performed baseline spontaneous pain, evoked pain, and cognitive testing. Subjects were administered aerosolized cannabis or placebo and the pain intensity and subjective “highness” score was measured during the first hour and for an additional 3 hours.
The researchers found that spontaneous pain scores were significantly different between doses (P < 0.001). Comparisons between placebo and low, medium, and high doses were significant (P = 0.031, 0.04, and < 0.001, respectively), as were those between high versus low and medium doses (both P < 0.001). The high dose had a significant effect on foam brush and von Frey evoked pain (P < 0.001). The high dose had a significant negative effect (impaired performance) on 2 of the 3 neuropsychological tests.
“This adds preliminary evidence to support further research on the efficacy of the cannabinoids in neuropathic pain,” the authors write.