How to Protect Your Nerves During Chemotherapy

By: Dr. Adam McLeod, ND, BSc (Hons)

A common side effect from chemotherapy is peripheral neuropathy which manifests as painful or uncomfortable symptoms in the peripheral nerves. It often manifests as pain, burning, tingling, loss of sensation, balance problems or sensitivity to temperature and touch. The significance of the symptoms varies depending on how badly the nerves were damaged from the drug. Usually the feet and hands are affected first but technically these concerns can manifest anywhere in the body. If left untreated this damage can be permanent.

There are some drugs such as paclitaxel which are well known to cause this uncomfortable side effect. When the cancer team discusses the different side effects of therapy, patients are often left with the impression that peripheral neuropathy is a normal side effect of chemotherapy. As a consequence when it starts happening, patients do not recognize it as a serious concern. What more patients need to be aware of is that if you are experiencing neuropathy then you must inform your oncologist and your oncology nurse so that the dose can be modified accordingly. Do not wait for them to tell you that you have neuropathy, you must take the initiative and inform them as soon as you experience these symptoms.

Many oncologists have this belief that the only way to prevent peripheral neuropathy is to reduce the dose of the drug causing this symptom. Of course modifying the dose is important to prevent damage to the nerves but there are many natural therapies which can help support nerve health as well. What is interesting about these natural supports is that they are well documented to make a substantial difference in some major studies published in the most mainstream oncology scientific journals.

These natural therapies help to support the health of nerves during and after chemotherapy and the sooner that these supports are implemented the better. There are many different nerve supports available but the ones that I will talk about in this article are L-glutamine, B-vitamins and ALA. Another therapy that I will discuss is cryotherapy to the extremities.

L-Glutamine:

Glutamine is an amino acid that can be used to help support the health of nerves during and after chemotherapy^1,2,3. In my experience this is particularly helpful with some of the intense chemotherapy regimens given to patients battling colon cancer. I have also found it to be more helpful when it is used to prevent neuropathy rather than waiting until the neuropathy has developed and then deciding to use it.

There is currently a controversy about the use of glutamine in cancer patients. Cancer cells uptake glutamine and it is metabolized by the cancer for a number of different pathways. Some people look at this information and jump to the conclusion that glutamine feeds the cancer. Yes, glutamine does feed cancer but glutamine also feeds every cell in the body. If the cancer does not get glutamine from the blood stream then it will cause muscles to waste away and get the amino acid from those tissues. The cancer will always find a way to get glutamine whether you supplement with it or not. The simplistic point of view that we should avoid everything that has potential to “feed cancer” is seriously flawed because our immune system desperately needs these same molecules as well. When it comes to the use of glutamine during chemotherapy, the benefits certainly outweigh the risks and this is particularly evident when we consider the health of the nerves.

B-Vitamins:

During chemotherapy the body often becomes rapidly depleted in water soluble B-vitamins¹¹. It is critical to make sure that you are adequately supplied with B-Vitamins prior to and during chemotherapy to adequately support the nerves. The vitamins that are most critical to prevent neuropathy are B1 (Benfotiamine) and B12 (Methylcobalamin)^4,5. The dosage of these nutrients makes a big difference and many of the low quality brands have completely insufficient doses. I have no idea why many of the popular low quality brands decided to put the same dose of all B-Vitamins (eg. 50mg of each B-Vitamin). Just because they share the letter “B” in their name does not mean that the metabolic requirement for each one is the same. Each B vitamin has a completely different function in the body so clearly some will be needed in greater quantities than others.

In my practice I regularly give B12 injections to patients who are undergoing any taxol chemotherapy. B12 is not an antioxidant and there are no realistic concerns about giving these shots regularly. Often the absorption of B-vitamins are impaired in cancer patients so oral supplementation is insufficient to achieve the desired doses. I have found that when given weekly these shots can dramatically support the health of the nerves. It is important to point out that you do not have to have a blood test which shows low B12 levels to justify the use of B12 injections. Vitamin B12 is a water soluble vitamin so if your levels are high then the excess will just be excreted in your urine. It is not uncommon for me to give these injections to patients who actually have high levels in their blood and their symptoms improve as a result. A test that demonstrates adequate amounts of B12 floating in your blood in no way indicates how effectively your body is actually utilizing the B12. It seems that many people during chemotherapy have a functional deficiency of B12 during chemotherapy, even if the actual concentration in the blood is normal or high.

Alpha Lipoic Acid (ALA):

This natural support has been shown to be a helpful nerve support with certain chemotherapies⁵. It is critical to recognize that ALA is not safe with all chemotherapies. You must have professional guidance when implementing any of these neurological supports into a cancer treatment plan. ALA helps to prevent neurological damage by supporting the health of the mitochondria. Every cell in the body has mitochondria which are responsible for generating energy and these delicate structures are often damaged by chemotherapy. The ALA helps to directly protect these components within nerve cells which can help to prevent neurological damage.

I have found ALA to be particularly helpful in cases where patients had diabetic neuropathy prior to starting chemotherapy. Clearly in these cases additional supports are needed because the nerves will be inherently vulnerable to any additional stressors. ALA has been extensively studied in the context of diabetic neuropathy and has consistently demonstrated a positive effect  in numerous studies⁶. This is an example of a natural therapy where the quality of the supplement makes a big difference. It can be administered orally or through an IV. If it is given orally then it must be the pure R form to be effective. If it is a racemic mixture then it will not be effective. When it is administered through an IV it must not be mixed with anything else and the entire line and bag must be completely protected from UV rays. Often the bag and line is wrapped in tin foil to prevent UV degradation of the ALA.

Cryotherapy on hands and feet during chemotherapy:

One of the most basic physiological concepts is how blood flow changes when the body is exposed to extreme temperatures. When our tissues are exposed to cold temperatures the blood vessels in the periphery (arms, hands, legs and feet) constrict dramatically to reduce blood flow to the peripheral regions of the body. The blood is shunted to the internal organs so that your core body temperature is preserved and this allows vital organs to continue to function optimally in cold temperatures. When the body is exposed to very warm temperatures then the opposite happens. The blood vessels in the periphery open up and blood is drawn away from the internal organs to the periphery of the body. This prevents vital organs from overheating and it allows heat to escape on the periphery of the body in the form of sweat.

The concept behind cryotherapy during chemotherapy is that if cold is applied to peripheral tissues then there will be less blood flow to the nerve endings that are vulnerable to the effects of chemotherapy. By this same logic it should also deliver more chemotherapy to the cancer (which is more often located in these internal organs rather than on the hands/toes) by fundamentally changing the flow of blood in the body. This concept makes perfect sense on the physiological level and I would recommend this to anyone who is particularly concerned about neuropathy developing in their hands or feet. There is an abundance of research that supports the use of this therapy on the hands or feet to prevent nail toxicity and peripheral neuropathy^7,8,9. In circumstances where patients wish to also preserve taste while reducing the risk of oral mucositis, it can be helpful to chew ice cubes during the infusion¹⁰. Of course this should not be done in cases of oral cancers but it is a helpful way to preserve taste by reduce blood flow to the tongue and mouth. This is a simple approach that in my opinion every patient should consider adding to their treatment plan.

Summary:

When used appropriately these neurological supports can be used in a synergistic manner to powerfully support nerve health. The sooner that these supports are used, the better chance of nerve recovery. The therapies that were discussed in detail here are only a fraction of the available therapies. Acupuncture, phosphatidyl-serine, acetyl-L-carnitine and glutathione are also used in specific circumstances to support nerve health. All of these supports must be used properly if you expect to have any positive results. In order to develop an effective nerve support protocol you must have professional guidance from a Naturopathic doctor who has experience supporting patients through chemotherapy.

Dr. Adam McLeod is a Naturopathic Doctor (ND), BSc. (Hon) Molecular biology, Motivational Speaker and International Best Selling Author. He currently practices at his clinic in Vancouver, British Columbia where he focuses on integrative cancer care. https://www.yaletownnaturopathic.com

References:

1) Wang, Wei-Shu, et al. “Oral glutamine is effective for preventing oxaliplatin-induced neuropathy in colorectal cancer patients.” The Oncologist 12.3 (2007): 312-319.

2) Savarese, Diane MF, et al. “Prevention of chemotherapy and radiation toxicity with glutamine.” Cancer treatment reviews 29.6 (2003): 501-513.

3) Vahdat, Linda, et al. “Reduction of paclitaxel-induced peripheral neuropathy with glutamine.” Clinical Cancer Research 7.5 (2001): 1192-1197.

4) Dizaye, Kawa F., and Chro Y. Qadir. “Effects of Benfotiamine and Methylcobalamin on Paclitaxel induced Peripheral neuropathy.” Middle East Journal of Internal Medicine 7.1 (2014).

5) Mondal, S., et al. “Comparative study among glutamine, acetyl-L-carnitine, vitamin-E and methylcobalamine for treatment of paclitaxel-induced peripheral neuropathy.” Clinical Cancer Investigation Journal 3.3 (2014): 213.

6) Foster, Tricia Stewart. “Efficacy and safety of α-lipoic acid supplementation in the treatment of symptomatic diabetic neuropathy.” The Diabetes Educator 33.1 (2007): 111-117.

7) Scotté, Florian, et al. “Multicenter study of a frozen glove to prevent docetaxel-induced onycholysis and cutaneous toxicity of the hand.” Journal of clinical oncology 23.19 (2005): 4424-4429.

8) Scotté, Florian, et al. “Matched case‐control phase 2 study to evaluate the use of a frozen sock to prevent docetaxel‐induced onycholysis and cutaneous toxicity of the foot.” Cancer 112.7 (2008): 1625-1631.

9) Eckhoff, L., et al. “Risk of docetaxel-induced peripheral neuropathy among 1,725 Danish patients with early stage breast cancer.” Breast cancer research and treatment 142.1 (2013): 109-118.

10) Karagözoğlu, Şerife, and Mehlika Filiz Ulusoy. “Chemotherapy: the effect of oral cryotherapy on the development of mucositis.” Journal of clinical nursing 14.6 (2005): 754-765.

11) Schloss, Janet M., et al. “Chemotherapy-induced peripheral neuropathy (CIPN) and vitamin B12 deficiency.” Supportive care in cancer: official journal of the Multinational Association of Supportive Care in Cancer 23.7 (2015): 1843.