Neuropathic Pain

What is neuropathic pain?

Neuropathic pain is pain caused by injury or damage to nerves.

How does it occur?

Neuropathic pain can be caused by:

• inflammation
• infections such as shingles or malaria
• cancer treatment (Many cancer treatments do not affect nerves, but a number of them do cause nerve damage that leads to numbness more than pain.)
• surgery
• tumors, which can surround a nerve and squeeze it or invade and destroy a nerve
• a herniated disk pressing on a nerve
• diseases such as diabetes or thyroid problems
• vitamin B-12 deficiency or folic acid deficiency
• decay or wearing out of the nerves by aging or a problem you have inherited
• brain injury, such as might be caused by a stroke.

What are the symptoms?

Neuropathic pain feels different from most other types of pain. It is often described as sharp, stabbing, or burning or like an electric shock. It may be worse at night. The pain may be constant after a stroke or if you have diabetic neuropathy of the feet and legs. The pain may come and go if you have trigeminal neuralgia (nerve pain in the face, teeth, mouth, or nasal cavity) or sciatic pain (a form of low back pain that runs down your leg, causing pain, numbness, or tingling in the leg).

Kinds of neuropathic pain include:

• Allodynia, which means that you get pain from something that does not normally cause pain. For example, this might be a breeze blowing across your arm or a sheet rubbing up against a leg.
• Hyperalgesia, which means feeling more pain than normal from something that does normally cause some pain. For example, you might feel like a searing iron has touched your arm when you just bump it.
• Dysesthesia, which is an uncomfortable feeling without true pain. For example, you might feel like pins and needles are poking your skin or that your feet are swollen or very fat or that worms are crawling on your skin.

Neuropathic pain can come from just one nerve. The kind of pain and where you feel it depends on what nerve is affected. Some of the more common pain problems are:

• trigeminal neuralgia (pain below the eye, over the cheek bone)
• occipital neuralgia (pain at the base of the skull, in back of the head)
• post-herpetic neuralgia (pain that you keep having after shingles, which is an infection of the nerves by the chickenpox virus).

How is it diagnosed?

Your healthcare provider will ask about your symptoms and medical history. He or she will examine you. Tests such as X-rays, blood tests, scans, and nerve conduction tests may be done to try to find the specific cause of the pain. Your healthcare provider may also refer you to a neurologist, neurosurgeon, or physiatrist for additional testing.

How is it treated?

Nonprescription and prescription pain medicines sometimes work well for neuropathic pain. If these medicines do not work well for you, your healthcare provider may prescribe antidepressants or antiseizure medicines that interfere with pain signals to the brain. They may be used alone or with other drugs. These medicines take days or weeks to work, so you must take the medicine every day on a set schedule to reduce the pain. These medicines rarely take away the pain completely, but they can help reduce it to a level you can tolerate.

Other treatments may include:

• massage
• heat or cold on the painful area (Each day one treatment might feel better than the other. If your ice-bag causes pain one day, switch to warm, moist heat or a heating pad for that day. Go back to ice another day.)
• biofeedback (a method of controlling your body's responses with your mind)
• electronic nerve stimulation devices (TENS)--these electrical stimulation devices come with 2, 4, or sometimes 8 electrical pads for your skin
• skin patches of numbing medicine, such as menthol (without prescription) or lidocaine (prescription needed)
• acupressure or acupuncture
• shots of local anesthetics, steroids, or other chemicals to block pain signals or decrease inflammation
• surgery to remove the root of the nerve, including electrosurgery, microsurgery, and radio wave surgery

Injection of drugs into or around the nerve can deaden the nerve, providing pain relief that is sometimes temporary and sometimes permanent. However, this may result in numbness in the area where the pain used to be.

If medicine does not help your pain, your provider will most likely refer you to a pain specialist or pain clinic.

Studies have not yet shown that herbal medicine treatments work well in the treatment of pain. Acupuncture or acupressure have also been studied and don't work very well. Some people might get wonderful relief, but that is not common. Capsaicin cream does work better than placebo creams, but the relief is not total.

How long will the effects last?

Some chronic pain problems do not go away. Other problems hurt for awhile, and then the pain mostly goes away. Often the pain goes away because the nerve is so damaged that it stops working altogether. When this happens, the pain starts to feel like cold or numbness.

How can I help take care of myself?

Neuropathic pain is a long-term, frustrating problem. You can help yourself by acknowledging that you will have some good days and some bad days. Going up and down with medicines or other treatments can be distracting and not very helpful with pain management. Often, your goal needs to be getting some pain relief and focussing on getting back to the things you enjoy or need to do.

Try hard to avoid narcotic pain medicines for neuropathic pain. The development of tolerance and the need for higher and higher doses can become a serious long-term problem if you start using narcotic (opioid) drugs as treatment for a chronic pain condition.