“It is unclear on the balance between the positive (pain relieving effects) and the negative,” Wallace noted. “However, there was actually minimal effects on psychomotor testing.”
His team measured psychomotor speed, attention and cognitive sequencing using what’s known as the Trail Making Test, a neuropsychological test consisting of visual attention and task switching. Researchers, using the Paced Auditory Serial Attention Test (PASAT), also measured participant attention, working memory and information processing speed.
“Cannabis does not treat the underlying disease process of diabetic neuropathy,” he said. “It will not prevent the progression of the disease nor will it reverse the process. It only relieves the pain that results from the neuropathy.
As for pain specialists using medical marijuana for chronic pain, many questions still remain. What can this treatment be used for? Up until May of this year, about 15 trials of medical cannibinoids have been conducted worldwide. These findings indicated effectiveness in reducing pain in patients with cancer, diabetes, fibromyalgia and neuropathy.
One lingering question that hasn’t been answered: Should physicians be allowed to prescribe medical cannabis to children? While nearly 65% of Americans approve of medical marijuana use for adults, only 36% agree that medical marijuana should be available for children, according to one report.3 The majority of survey respondents also noted that medical cannabis should not be used in front of children who are under the age of 18. When children do use the drug, however, it’s typically not inhaled — it’s normally available in liquid, non-psychoactive form, such as the cannabinoid cannabidiol (CBD).
More recently, a recent study in JAMA concluded that there was moderate-quality evidence suggesting that cannabinoids could benefit those with chronic neuropathic or cancer pain. The study also revealed, however, that there was low-quality evidence for no effect on psychosis. There was very low-level evidence that cannabinoids affected depression.
“More studies are needed on chronic delivery,” Wallace said. “And more studies are needed on cannabidiol (the non psychoactive component of marijuana). Our study used cannabis that had very low levels of cannabidiol.”
1. Tesfaye S, et al. Painful Diabetic Polyneuropathy. 2015; doi: 10.1007/978-1-4614-6299-6_13.
2. Wallace M, et al. J. Pain. 2015; doi: 10.1016/j.jpain.2015.03.008.