Neuropathy and Medical Cannabis

September 2021 by Sandy Yanez

Neuropathy is a condition that results from damage to or dysfunction of the nervous system. The system’s complex chain of neurons is how our brain communicates with the rest of our body. The nervous system consists of two parts; the central nervous system, which is the brain and spinal cord, and the peripheral system, which is the nerves and nerve pathways throughout the body and the limbs.

Most often, the damage exists in the peripheral nervous system, although brain injury, such as stroke, can also result in neuropathic symptoms. The symptoms of neuropathy depend on the underlying nerves whose function has been affected.

Neuropathy that damages sensory nerves can cause numbness, weakness, stabbing or burning pain – symptoms that may worsen if not treated early. If there has also been damage to the nerves that convey the sense of touch, vibration, and temperature – patients may experience tingling, numbness, or the sense of wearing an invisible glove or sock over their hands or feet.

If there is damage to motor nerves that control stability and movement, patients may have a lack of coordination, weakness, or cramping.

Finally, if the autonomic nerves that regulate internal organ function have been damaged, patients may experience a reduction in saliva, tears, perspiration, or other organ or gland dysfunction.

 

Traditional treatment

The goal has been aimed towards managing the condition causing the neuropathy and to relieve symptoms. Traditionally treatments include opioids, anti-seizure medications, topical creams, and antidepressants – which all have side effects ranging from addiction to constipation.

Besides medications used, various therapies and procedures may help ease the signs and symptoms of neuropathy. Transcutaneous electrical nerve stimulation (TENS) units are electrodes placed on the skin to deliver a gentle electric shock to distract the pain. Plasma exchanges involve removing and cleaning your blood or intravenous immune globulin therapy, where you receive high levels of proteins that work as antibodies in an attempt to control the neuropathy.

 

How can cannabis help?

There have been several studies done that conclude cannabis is helpful in treating neuropathy.

A review published in the AMA Journal of Ethics concluded that cannabis is as effective as the traditional agents currently used to treat neuropathic pain. The studies were conducted with low to medium THC content at 2 to 9 percent.

The Journal of Pain published a study demonstrating low-dose of less than 2 percent THC significantly improved neuropathic pain when compared to medium-dose and placebo cannabis. Most in this study had already experienced poor results with conventional neuropathic treatments.

A similar study conducted and published in the Canadian Medical Association Journal looked at several patients who were assigned three different strengths of cannabis to manage post-traumatic and post-surgical neuropathy pain and found a single inhalation of 9% THC three to five times a day reduced the intensity of pain and improved sleep.

Cannabis Pharmacy author Michael Backes writes that these studies are particularly significant because the best results were observed at the lowest dose, highlighting “the unexpected medical effectiveness of cannabis dosages that are far below those commonly consumed within the medical community.”

A study published in 2020 found that cannabidiol (CBD) used as a topical demonstrated a significant improvement in pain and other disturbing sensations in patients with peripheral neuropathy. The treatment was well tolerated and provided a more effective alternative compared to other current treatments in peripheral neuropathy.

Another study concluded that CBD suppresses chronic inflammatory and neuropathic pain directly without building tolerance. In addition, CBD helped reduce muscle spasms, which can be a symptom of neuropathic damage.

Please keep in mind that CBD is not FDA regulated and there is a vast amount of CBD oils out there that are fake. No matter where you purchase your CBD, make sure it is lab tested. There should be labs testing information on the bottle or ask to see a certification of analysis (COA). Just because your doctor or even dispensary sells it, that does not mean it’s pure CBD.

 

How Does Cannabis Work for Nerve Pain?

The endocannabinoid system plays an essential role in regulating neuroplasticity and homeostasis of the central nervous system. It also works to modulate pain transmission in the nerve pathways. The body produces its own endocannabinoids on demand in the central nervous system, which acts as a circuit breaker to reduce pain.

After a nerve injury, neurons can become more reactive and responsive. This can cause a series of cellular events that lead to the development of painful nerve endings. Cannabinoids can reduce nerve pain by altering these cellular functions. Cannabinoids like THC and CBD activate the CB1 and CB2 receptors and help regulate neurotransmitters and the central nervous system, helping to alleviate pain. Cannabis also plays a role in the endorphin system and can reduce a patient’s perception of pain, making it feel less intense and easier to deal with.

Putting it all together

Pain relief is the main benefit of cannabis as a neuropathy treatment. Studies show that individuals with neuropathic pain experience pain reduction while undergoing THC/CBD therapy. Pain intensity decreases with long-term use.

Other benefits that individuals with neuropathy may experience with THC/CBD therapy include improved sleep, positive changes in mood, and improved quality of life. Cannabis has been shown to have an antidepressant-like effect due to changes it creates in parts of the brain associated with mood and pain memory. The combination of pain relief and reduced depression can improve overall quality of life. Another benefit of cannabis is that it may reduce the amount or frequency of opioid medications needed for pain relief. It also tends to have few to no side effects.

 

Conclusion

While there is proof through studies that cannabis, mainly THC and CBD, can treat neuropathic pain, there are dozens of other cannabinoids that can reduce chronic pain as well. Cannabis has been known to help people with many physical and mental disorders – lessen feelings of pain and live more satisfying lives.

References

Backes, M. (2017) Cannabis pharmacy: The practical guide to medical marijuana. New York: Black Dog & Leventhal Publishers.

Grant, I.(2013).Medicinal cannabis and painful sensory neuropathy. AMA Journal of Ethics. 2013;15(5):466-469. DOI 10.1001/virtualmentor.2013.15.5.oped1-1305.

Ware, M., Wang, T., Shapiro, S., Robinson, A., et. al. (2010) Smoked cannabis for chronic neuropathic pain: A randomized controlled trial. CMAJ, 182(14)694-701. DOI: https://doi.org/10.1503/cmaj.091414

Wilsey, B., Marcotte, T., Deutsch, R., Gouaux, B., et al., (2012). Low-dose vaporized cannabis significantly improves neuropathic pain. The Journal of Pain, 14;(2)136-148. https://doi.org/10.1016/j.jpain.2012.10.009

Xiong, W., Cui, T., Cheng, K., Yang, F., Chen, S. R., Willenbring, D., Guan, Y., Pan, H. L., Ren, K., Xu, Y., & Zhang, L. (2012). Cannabinoids suppress inflammatory and neuropathic pain by targeting α3 glycine receptors. The Journal of experimental medicine, 209(6), 1121–1134. https://doi.org/10.1084/jem.20120242

Xu, D. H., Cullen, B. D., Tang, M., & Fang, Y. (2020). The Effectiveness of Topical Cannabidiol Oil in Symptomatic Relief of Peripheral Neuropathy of the Lower Extremities. Current pharmaceutical biotechnology, 21(5), 390–402. https://doi.org/10.2174/1389201020666191202111534