Smoked cannabis for chronic neuropathic pain: a randomized controlled trial
A great paper just came out in the Canadian Medical Association Journal, dealing with the ability of cannabis to combat neuropathic pain. Neuropathic pain is thought to be caused by damage to the nervous system, and often does not respond to conventional painkillers. It is estimated that 1-2% of the adult population is affected, and patients with this chronic pain have reported using smoked cannabis to relieve pain, improve sleep and improve mood.
Suffice to say that most of the time this isn’t suggested by doctors and dispensed by prescription. So does it actually work? 21 adults with post-traumatic or postsurgical neuropathic pain completed the study, and were randomly assigned to receive cannabis at four potencies (0%, 2.5%, 6% and 9.4% THC). They assigned the various strengths of cannabis as part of a “crossover trial”, where each subject would receive one of the concentrations randomly for a two week period. After four two-week periods and random “crossovers” to other potencies, everyone had tried every potency.
Participants inhaled a single 25-mg dose of cannabis through a pipe three times daily for the first five days in each two-week period, followed by a nine-day washout period before the next trial. Daily average pain intensity was measured using an 11-point scale, and effects on mood, sleep, quality of life, and adverse events were recorded.
And the results? Turns out that you need decent pot for pain relief, but it doesn’t have to be an insanely potent strain. Lower potency cannabis did not significantly reduce pain, but the 9.4% THC cannabis reduced pain, improved ability to fall asleep, and improved quality of sleep. The beautiful outcome is that cannabis containing 10% THC is widely available and only 75mg a day (slightly over two grams a month) is needed to cause statistically significant improvements for those suffering chronic pain.
Mark A. Ware, Tongtong Wang, Stan Shapiro, Ann Robinson, Thierry Ducruet, Thao Huynh, Ann Gamsa, Gary J. Bennett, Jean-Paul Collet, Smoked cannabis for chronic neuropathic pain: a randomized controlled trial, Canadian Medical Association Journal, Volume 182, Number 14, 2010, Pages 694-701.
