1. What treatments can cause Peripheral Neuropathy?
Peripheral neuropathy is often caused by medications used to treat cancer, but it can also be caused by radiation therapy, surgery for cancer, the tumor pressing on nerves, infections or chemicals that tumors release.
The following medications that are used in treating cancer can cause peripheral neuropathy:
- Platinum drugs, like oxaliplatin (Eloxatin), cisplatin (Platinol), and carboplatin (Paraplatin)
- Taxanes, including drugs like docetaxel (Taxotere) and paclitaxel (Taxol, Abraxane)
- Vinca alkaloids: vinorelbine (Navelbine), vincristine (Oncovin, Vincasar), and vinblastine (Velban)
- Podophyllotoxins, which includes drugs such as teniposide (Vumon) and etoposide (Etopophos, VePesid, Toposar, VP-16)
- Epothilones can cause peripheral neuropathy. This includes drugs like ixabepilone (Ixempra)
- Lenalidomide (Revlimid) and thalidomide (Thalomid)
- Interferon can cause peripheral neuropathy
- Bortezomib (Velcade)
- Fluorouracil (Adurcil, 5-FU)
- Methotrexate (Trexall, Rheumatrex, MTX, Amethopterin)
- Cytarabine (Cytosar-U) can cause peripheral neuropathy
2. What are symptoms of Peripheral Neuropathy?
There are three types of peripheral nerves: sensory, motor, and autonomic and these types of nerves cause different symptoms when they are damaged by peripheral neuropathy. If damage occurs to sensory nerves, symptoms may include numbness, tingling and/or pain. If the motor nerves are damaged, you may have problems with your balance or feel weak. If your autonomic nerves are involved in peripheral neuropathy symptoms may include dizziness or constipation.
Symptoms of peripheral neuropathy usually begin in the toes and fingers and progress inward or upward to the feet and hands, then to the legs and arms. It can eventually become difficult to grasp items, button your shirt, maintain your balance and walk.
Symptoms can start to develop any time after therapy is started and may occur suddenly. The symptoms of peripheral neuropathy are typically fairly mild when they first begin and gradually become worse. The symptoms also improve slowly once treatment is stopped, usually over several months. Sometimes, permanent nerve damage has occurred and the symptoms never totally resolve.
Common symptoms of peripheral neuropathy include:
- Numbness, tingling, burning
- Muscle weakness and cramps
- Pain that may be constant or intermittent and may be stabbing or shooting
- Loss of sensation of touch
- Loss of temperature sensation
- Increased sensitivity to temperature
- Loss of balance and dizziness
- Difficulty walking
If you experience any symptoms of peripheral neuropathy, notify your physician right away
3. Am I at an increased risk for Peripheral Neuropathy?
Not all patients treated with chemotherapy develop peripheral neuropathy but nearly one-third to 40% do develop some symptoms of the disorder. It cannot be predicted who will develop nerve disorders related to cancer treatments but some risk factors make you more likely to develop peripheral neuropathy.
Factors that increase the risk of peripheral neuropathy include:
- A past history of radiation therapy, chemotherapy or surgery
- A long course of therapy or a high dose of chemotherapy make peripheral neuropathy more likely to develop
- Taking 2 or more drugs that have a potential for causing neuropathy
- A history of alcohol abuse
- Having other medical conditions such as diabetes, AIDS or HIV, lymphoma, multiple myeloma, or breast or lung cancer
- Being severely malnourished
- Having a history of nerve damage from a prior illness or injury increases your risk of peripheral neuropathy
4. How is Peripheral Neuropathy diagnosed?
If you have symptoms of peripheral neuropathy, tell your doctor. Some simple tests may be performed such as a test of your reflexes, your muscle strength and your coordination and balance. Your doctor may also recommend nerve conduction studies which measure the speed and strength of the electrical signals your nerves send to the muscles when a small shock is delivered.
5. Can Peripheral Neuropathy be avoided?
It may help to decrease the dose of the cancer drugs being given, but there is no known way to prevent peripheral neuropathy in patients who are receiving chemotherapy drugs known to cause the condition. There are studies being conducted to test various ways of preventing the disorder without minimizing the effectiveness of the treatment for cancer.
Many supplements and medications are being studied for the prevention of peripheral neuropathy in cancer patients. More research is necessary because the results have not been conclusive. Some of these prevention treatments being studied include:
- Infusions of calcium and magnesium
- Alpha-lipoic acid
- Amifostine (Ethyol)
- Org 2766
- Vitamins B1 and B12
- Vitamin E
Do not take any vitamins or supplements without first checking with your doctor. They can make your chemotherapy less effective and can cause adverse side effects if not taken in the correct dosage. If peripheral neuropathy symptoms develop during your treatment, it may be stopped. Treatment can resume when you are feeling better or if cancer growth is detected again in the future. A break in treatment can sometimes prevent peripheral neuropathy from progressing. If treatment is not stopped, peripheral neuropathy might continue and the nerve damage might become permanent.
6. How is Peripheral Neuropathy treated?
The treatment for peripheral neuropathy is aimed at controlling the symptoms because there are no treatments that will correct nerve damage once it has occurred. Many treatments are not proven to be effective and have their own adverse effects. There are some combinations of therapies, however that are effective in helping the symptoms.
Some of the same supplements and medications that are being tested for the prevention of peripheral neuropathy are also being used for treatment.
Some of the drugs used to help control the symptoms of peripheral neuropathy include:
- Antidepressants, such as venlafaxine for numbness and tingling
- Anticonvulsants, such as carbamazepine for nerve pain
- Muscle-relaxants, such as baclofen for painful muscle spasms
- Analgesics, such as ibuprofen
- Steroids such as prednisone to decrease painful inflammation. These can only be used for a short time for peripheral neuropathy due to their potential to cause serious side effects
- Opioids or narcotics for severe pain
- Capsaicin cream (made from chili peppers)
- Laxatives or stool softeners for occasional constipation
- Lidocaine patches
- A gentle laxative for constipation
Your doctor may recommend some dietary supplements, such as:
- A multi-vitamin that contains the B vitamins
- Extra folic acid
Other treatments that may help manage your symptoms of peripheral neuropathy include:
- Transcutaneous electrical nerve stimulation (TENS) In this therapy, nerves are gently pulsed with a gentle electrical current which stimulates the body to release endorphins
- Physical and/or physical therapy
- Meditation, guided imagery, distraction techniques and relaxation
7. What else should I do?
If your feet and hands are numb due to peripheral neuropathy, you are at increased risk for injuries. These injuries can go unnoticed and quickly become infected, so protecting yourself is essential. Here are some things you can do to protect yourself from injuries related to peripheral neuropathy:
- Wear protective shoes to protect your feet. Never go barefoot.
- Protect your hands from injury by wearing gloves when working with your hands
- Inspect your hands and feet for redness, cuts, bruises, blisters, wounds, and other injuries at least daily
- Use extra caution when handling hot food or liquids or sharp objects
- Use extra caution on stairs and steps; always use the handrail
- Use non-slip surfaces in the shower. Wear swim shoes when swimming in public pools or lakes
- Lower your hot water heater temperature to 120°F or lower to prevent burns
- Use a cane or other assistive device if you feel weak or unsteady
- Ask for help
- Avoid alcohol, which can make peripheral neuropathy worse
- Keep the thermostat in your home at a comfortable level. Hot or cold temperatures can make symptoms of peripheral neuropathy worse.