Medical Cannabis for Neuropathic Pain
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Purpose of Review
Many cultures throughout history have used cannabis to treat a variety of painful ailments. Neuropathic pain is a complicated condition that is challenging to treat with our current medications. Recent scientific discovery has elucidated the intricate role of the endocannabinoid system in the pathophysiology of neuropathic pain. As societal perceptions change, and legislation on medical cannabis relaxes, there is growing interest in the use of medical cannabis for neuropathic pain.
We examined current basic scientific research and data from recent randomized controlled trials (RCTs) evaluating medical cannabis for the treatment of neuropathic pain. These studies involved patients with diverse etiologies of neuropathic pain and included medical cannabis with different THC concentrations and routes of administration. Multiple RCTs demonstrated efficacy of medical cannabis for treating neuropathic pain, with number needed to treat (NNT) values similar to current pharmacotherapies.
Although limited by small sample sizes and short duration of study, the evidence appears to support the safety and efficacy of short-term, low-dose cannabis vaporization and oral mucosal delivery for the treatment of neuropathic pain. The results suggest medical cannabis may be as tolerable and effective as current neuropathic agents; however, more studies are needed to determine the long-term effects of medical cannabis use. Furthermore, continued research to optimize dosing, cannabinoid ratios, and alternate routes of administration may help to refine the therapeutic role of medical cannabis for neuropathic pain.
KeywordsMedical marijuana Neuropathic pain Cannabis THC CBD Cannabinoid
Compliance with Ethical Standards
Conflict of Interest
Gemayel Lee, Brittany Grovey, Tim Furnish, and Mark Wallace declare no conflict of interest.
Human and Animal Rights and Informed Consent
All reported studies/experiments with human or animal subjects performed by the authors have been previously published and complied with all applicable ethical standards (including the Helsinki declaration and its amendments, institutional/national research committee standards, and international/national/institutional guidelines).
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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