Neuropathic pain results when the peripheral or central nervous system is damaged or dysfunctional. This can be triggered by trauma, infections or nervous system disorders. Often it comes on as pain that seems to be more intense than a typical injury to the skin. There are several syndromes associated with this condition including: postherpetic neuralgia, root avulsions, painful traumatic mononeuropathy, painful polyneuropathy (particularly due to diabetes), central pain syndromes (potentially caused by any lesion at any level of the nervous system), postsurgical pain syndromes, and complex regional pain syndrome. A 2007 study estimated that 170 to 270 million people around the world suffer from peripheral neuropathy (e.g., phantom limb syndrome and complex regional pain syndrome) and neuropathic pain.
Neuropathic pain is described as numbing or burning along with sensations of tingling, electric shock, crawling, itching, or shooting. Mild pain stimuli are perceived as very painful. Pain on one side of the body may also be felt on the other side. The pain may increase to include larger and larger areas of the body. This condition is difficult to treat and often requires a combination of medicine, counseling and often some form of alternative therapy.
Peripheral neuropathy is a disturbance in the function of a nerve or a group of nerves outside of the brain and spinal cord (called the peripheral nerves). It can result in pain, numbness, tingling, a burning sensation or a feeling of itching or crawling in the affected area. The damage to these nerves can be caused by disease, injury, poisoning or malnutrition. Often fewer nutrients are able to reach the nerve tissue due to poor circulation. The nerves that are furthest from the heart, such as those in the hands and feet, are the most likely be affected. People with diabetes can suffer peripheral neuropathy because of circulatory problems caused by the illness. Another condition, peripheral vascular disease (the fatty buildup the walls of arteries) also leads to poor circulation.
Neuropathic Pain and Cannabis
NOTE FOR FIRST TIME READERS: Cannabinoids – such as THC, CBD – and terpenes are the main medically active components in cannabis (aka marijuana). For more information on these components, and much more about the plant, see our section on the Science of Cannabis.
The treatment of pain, particularly neuropathic pain, is one of the major therapeutic applications of cannabis that is currently under investigation. FDA-approved research showed that inhaled cannabis can significantly alleviate neuropathic pain. In one study HIV patients who smoked cannabis reduced nerve pain by more than 30% when compared to a placebo. Another study had volunteers given injections followed by medium doses of cannabis, which significantly reduced the discomfort caused by the shot. A third study reported patients who were unresponsive to standard pain therapies were able to ease their neuropathic pain when they inhaled cannabis.
In fact, patients often report that they are better able to control their neuropathic pain with cannabis than with other medications. Some are even able to decrease or eliminate their need for Neurontin or Lyrica. Sativex, a cannabis-based medicine has been approved in Great Britain for use in the treatment of neuropathic pain in Multiple Sclerosis. With the increase in research around this topic, cannabis is slowly becoming accepted as an effective option in the treatment of neuropathic pain.
To achieve the best results using cannabis to treat neuropathic pain and neuropathy, patients need to follow a constant daily regimen for weeks or months. For example, post-herpetic neuralgia may last for months, but over time, with cannabis therapy, the pain does reduce. CBD and THC are both useful for neuropathy, but THC may be more effective for pain. Dosages may range up to 25 mg of cannabinoid three times per day.
Abrams D, et al. Cannabis in painful HIV-associated sensory neuropathy. Neurology. 2007, 68: 515-521.
Wilsey B, et al. A randomized, placebo-controlled, crossover trial of cannabis cigarettes in neuropathic pain. J Pain. 2008, 9(6): 506-21.
Wilsey, B, Marcotte, T, Deutsch, R, Gouaux, B, Sakai, S, Donaghe, H. Low-dose vaporized cannabis significantly improves neuropathic pain. J Pain. 2013, 14(2): 136-48.
Ellis RJ, et al. Smoked medicinal cannabis for neuropathic pain in HIV: A randomized, cross-over clinical trial. Neuropsychopharmacology. 2008, www.cmcr.ucsd.edu/geninfo/Ellis_2008.pdf
Rog DJ et al. Oromucosal δ9-tetrahydrocannabinol/cannabidiol for neuropathic pain associated with multiple sclerosis: an uncontrolled, open-label, 2-year extension. Clinical Therapeutics. 2007, 29: 2068-2079.