Cancer can be a devastating diagnosis. Chemotherapy is frequently included as part of many treatment plans for different types of cancer. Unfortunately, the way chemotherapy works creates not only damage to the cancer cells, but also damages some of the healthy cells. This results in painful side effects that are often equally difficult to manage and treat - such as neuropathy.
When caused by drugs of any kind, this specific type of neuropathy is called chemotherapy-induced peripheral neuropathy. This type of peripheral neuropathy is arguably one of the most difficult as a result of the widespread damage to the nerves of the hands and feet. The destruction of the small nerves and blood vessels in the hands and feet causes symptoms such as pain, tingling, burning, shocks, among other constant problems. Some patients may have difficulty doing simple things that are a part of everyday life - things that they were able to do before chemo - such as simply walking or maintaining their balance.
There are very few treatments for the symptoms of chemotherapy-induced neuropathy. Most cancer patients are aware of the FDA-approved treatments for neuropathy such as gabapentin or pregabalin. The shortage of treatment options has led physicians and researchers on a path to expand the number of ways to alleviate the pain caused by peripheral neuropathy. For this reason, a group of physicians published a case series on the use of different chemicals in marijuana (called cannabinoids) to treat neuropathic pain in patients with peripheral neuropathy.
Recent Research on THC/CBD in Peripheral Neuropathy
The case series, published in 2021 in Integrative Cancer Therapies, concludes that the use of skin preparations infused with cannabinoids may be helpful in chemotherapy-induced neuropathic pain. The report includes patients that have used different types of marijuana derived topical preparations, including THC oil or CBD, It notes that only one of the patients reports having side effects that were temporary and those side effects resolved without any intervention. Almost all of the patients had previously tried medications and a few of them tried alternative medicine treatments such as acupuncture.
The treatment concepts highlighted by the case series is nothing new - physicians have been aware of the treatment potential of THC and CBD for neuropathic pain. In fact, a paper published in Neuropsychopharmacology in 2018 outlines the scientific basis for how THC and CBD work to relieve pain. Unfortunately, the legal landscape in the U.S. has made it extremely difficult for the scientific and medical community to research marijuana derivatives, which has resulted in the number of randomized trials for different indications to be few in number.
In short, there is some evidence that marijuana derivatives has help alleviate neuropathic pain in chemotherapy-induced peripheral neuropathy. Whether this benefit will translate to other forms of neuropathy, such as diabetic neuropathy, is still to be determined. However, the generally mild side effect profile of THC and CBD as treatments brings a large amount of promise.
D'Andre S, McAllister S, Nagi J, Giridhar KV, Ruiz-Macias E, Loprinzi C. Topical Cannabinoids for Treating Chemotherapy-Induced Neuropathy: A Case Series. Integr Cancer Ther. 2021 Jan-Dec;20:15347354211061739. doi: 10.1177/15347354211061739. PMID: 34841942; PMCID: PMC8646190.
Donvito G, Nass SR, Wilkerson JL, Curry ZA, Schurman LD, Kinsey SG, Lichtman AH. The Endogenous Cannabinoid System: A Budding Source of Targets for Treating Inflammatory and Neuropathic Pain. Neuropsychopharmacology. 2018 Jan;43(1):52-79. doi: 10.1038/npp.2017.204. Epub 2017 Aug 31. PMID: 28857069; PMCID: PMC5719110.