Cannabinoid medicine has gained popularity over the last few decades with the new and emerging research that has been conducted. Research shows that the endocannabinoid system is becoming a valuable therapeutic tool for a variety of conditions and diseases, including neuropathic pain.
First off, what is neuropathic pain? Neuropathic pain is due to a damaged or dysfunctional nervous system, triggering inflammation within our nervous tissue that results in amplified pain that can be described as sharp pain, numbness, tingling, and even burning sensations (Costigan, Scholz, Woolf, 2009). These lesions to our somatosensory nervous system has the potential to alter our nervous tissues structure and function, leading to ectopic generation of action potentials, facilitation and disinhibition of synaptic transmission, loss of synaptic connectivity and formation of new synaptic circuits and neuronal interactions, which can contribute to interrupted messages being sent and received, neuroinflammation (persistent pain), and neurodegeneration (Costigan, Scholz, Woolf, 2009).
Common causes of neuropathic pain that results from nerve damage includes medications, chemotherapy, vitamin deficiencies, alcoholism (depletes nutrients), multiple sclerosis (MS), Parkinson’s Disease (PD), diabetes, shingles, HIV/AIDS, fibromyalgia, strokes, autoimmune diseases, and damage to the spinal cord and nerves themselves (injury) (Costigan, Scholz, Woolf, 2009). It is estimated that nearly 16 million people in America alone deal with neuropathic pain, which means that 16 million people are suffering, most likely turning to pain medications and OTC medications, further leading to a deteriorated condition (Yawn, Wollan, Weingarten, Watson, Hooten, Melton, 2009).
Treatment is aimed at suppressing symptoms (ie. pain) and reducing neuroinflammation in the nervous tissue (brain, spinal cord, and peripheral nerves) but we need to take it a step further to include disease-modifying strategy focused on the prevention of maladaptive plasticity (harmful neural changes in the brain) by addressing underlying factors that make us more susceptible to these neuronal changes and diseases that affect nervous tissue (Yawn, Wollan, Weingarten, Watson, Hooten, Melton, 2009). The problem with conventional medicine is that medications fall short in providing relief for pain management and neuroinflammation, hence why 16 million people (and growing) are dealing with neuropathic pain daily.
The endocannabinoid system proves to be a valuable tool to address neuroinflammation due to the presence of CB1 (predominantly) and CB2 receptors (to a lesser degree) in our nervous tissue. Nociceptors are the actual receptors present in our skin, bones, joints, and blood vessels that sense pain. These pain receptors have CB1 and TRP channels on these sensory nerve endings that can help us address pain directly. CB1 receptors are located at synapses all along the ascending and descending pain pathways (glutamatergic projection neurons, inhibitory neurons) leading to activation of these CB1 receptors and transient receptor potential (TRP) channels (more specifically TRPV1), helping to provide analgesic (pain) relief. What this means is that we can use cannabinoids like CBD and THC to activate CB1 and CB2 receptors in our nervous tissue, helping to address pain and reduce neuroinflammation as well as protecting nervous tissue from further deterioration of nervous tissue (Walter, Stella, 2004). Taking an approach for treatment (managing symptoms via analgesic properties) as well as prevention (by offering anti-inflammatory properties that have the potential to reduce neuroinflammation), gives cannabinoid therapy a bright future for our healthcare system.
Cheers to advances in medicine when it comes to dealing with neuropathic pain. One amazing plant with seemingly endless uses. Now, that’s what I call medicine!
References
1.Costigan, M., Scholz, J., & Woolf, C. J. (2009). Neuropathic pain: a maladaptive response of the nervous system to damage.Annual review of neuroscience,32, 1–3
2.https://doi.org/10.1146/annurev.neuro.051508.1355312.Walter, L., & Stella, N. (2004). Cannabinoids and neuroinflammation.British journal of pharmacology,141(5), 775–785.https://doi.org/10.1038/sj.bjp.0705667
3.Wilsey B, Marcotte T, Deutsch R, Gouaux B, Sakai S, Donaghe H. Low-Dose Vaporized Cannabis Significantly Improves Neuropathic Pain.The journal of pain. 2013;14(2):136-148. doi:10.1016/j.jpain.2012.10.009
4.Yawn, B. P., Wollan, P. C., Weingarten, T. N., Watson, J. C., Hooten, W. M., & Melton, L. J., 3rd (2009). The prevalence of neuropathic pain: clinical evaluation compared with screening tools in a community population.Pain medicine (Malden, Mass.),10(3), 586–593. https://doi.org/10.1111/j.1526-4637.2009.00588.x
