Peripheral neuropathy often causes numbness and pain in your hands and feet. People typically describe the pain of peripheral neuropathy as tingling or burning, while they may compare the loss of sensation to the feeling of wearing a thin stocking or glove. Peripheral neuropathy is caused by nerve damage. It can result from such problems as traumatic injuries, infections, metabolic problems and exposure to toxins. One of the most common causes is diabetes. In many cases, peripheral neuropathy symptoms improve with time — especially if it's caused by an underlying condition that can be treated. A number of medications are often used to reduce the painful symptoms of peripheral neuropathy.

Complications of Peripheral Neuropathy

• Reduced feeling. Because parts of your body may be numb, you may be less likely to feel temperature changes or an injury.
• Infection. Make sure to check your feet, as well as any other areas lacking usual sensation, regularly so that you can treat minor injuries before they become infected. This is especially important for people with diabetes, who tend to heal more slowly.

Causes of Peripheral Neuropathy

It's not always easy to pinpoint the cause of peripheral neuropathy, because a number of factors can cause neuropathies. These factors include:

• Trauma or pressure on the nerve. Traumas, such as motor vehicle accidents, falls or sports injuries, can sever or damage peripheral nerves. Nerve pressure can result from using a cast or crutches, spending a long time in an unnatural position, or repeating a motion many times — such as typing.
• Diabetes. When damage occurs to several nerves, the cause frequently is diabetes. At least half of all people with diabetes develop some type of neuropathy.
• Vitamin deficiencies. B vitamins — B-1, B-6 and B-12 — are particularly important to nerve health. Vitamin E and niacin also are crucial to nerve health.
• Alcoholism. Many alcoholics develop peripheral neuropathy because they have poor dietary habits, leading to vitamin deficiencies.
• Infections. Certain viral or bacterial infections can cause peripheral neuropathy, including Lyme disease, shingles (varicella-zoster), Epstein-Barr, hepatitis C and HIV/AIDS.
• Autoimmune diseases. These include lupus, rheumatoid arthritis and Guillain-Barre syndrome.
• Other diseases. Kidney disease, liver disease and an underactive thyroid (hypothyroidism) also can cause peripheral neuropathy.
• Inherited disorders. Examples include Charcot-Marie-Tooth disease and amyloid polyneuropathy.
• Tumors. Growths can form directly on the nerves themselves, or tumors can exert pressure on surrounding nerves. Both cancerous (malignant) and noncancerous (benign) tumors can contribute to peripheral neuropathy.
• Exposure to poisons. These may include some toxic substances, such as heavy metals, and certain medications — especially those used to treat cancer (chemotherapy).

Signs & Symptoms of Peripheral Neuropathy

Your nervous system is divided into two broad categories. Your central nervous system consists of your brain and spinal cord. All the other nerves in your body are part of your peripheral nervous system. Peripheral neuropathy affects those nerves, which include:

• Sensory nerves to receive feelings such as heat, pain or touch
• Motor nerves that control how your muscles move
• Autonomic nerves that control such automatic functions as blood pressure, heart rate, digestion and bladder function

Most commonly, peripheral neuropathy may start in the longest nerves — the ones that reach to your toes. Specific symptoms vary, depending on which types of nerves are affected. Signs and symptoms may include:

• Gradual onset of numbness and tingling in your feet or hands, which may spread upward into your legs and arms
• Burning pain
• Sharp, jabbing or electric-like pain
• Extreme sensitivity to touch, even light touch
• Lack of coordination
• Muscle weakness or paralysis if motor nerves are affected
• Bowel or bladder problems if autonomic nerves are affected

Diagnosis of Peripheral Neuropathy

Peripheral neuropathy isn't a single disease, but rather a symptom with many potential causes. For that reason it can be difficult to diagnose. To help in the diagnosis, your doctor will likely take a full medical history and perform a physical and neurological exam that may include checking your tendon reflexes, your muscle strength and tone, your ability to feel certain sensations, and your posture and coordination.

Blood tests

Your doctor may also request blood tests to check your:

• Vitamin levels
• Thyroid function
• Blood sugar levels
• Liver function
• Kidney function

Electromyography

This test measures the electrical signals in peripheral nerves, and the transfer of that signal to muscles. As a part of this test, you'll be asked to have a nerve conduction study, which measures how quickly your nerves carry electrical signals. A nerve conduction study can be used to diagnose carpal tunnel syndrome and other peripheral nerve disorders.

Nerve biopsy

Additionally, your doctor may recommend a nerve biopsy, a procedure in which a small portion of a nerve is removed and examined for abnormalities. But even a nerve biopsy may not always reveal what's damaging your nerves.

Imaging tests

Your doctor may also request a CT scan or MRI to look for herniated disks, tumors or other abnormalities.

Treatments of Peripheral Neuropathy

One goal of treatment is to manage the condition causing your neuropathy. If the underlying cause is corrected, the neuropathy often improves on its own. Another goal of treatment is to relieve the painful symptoms. Many types of medications can be used to relieve the pain of peripheral neuropathy:

• Pain relievers. Mild symptoms may be relieved by over-the-counter pain medications. For more severe symptoms, your doctor may recommend prescription painkillers. Drugs containing opiates, such as codeine, can lead to dependence, constipation or sedation, so these drugs are generally prescribed only when other treatments fail.
• Anti-seizure medications. Drugs such as gabapentin (Neurontin), topiramate (Topamax), pregabalin (Lyrica), carbamazepine (Tegretol) and phenytoin (Dilantin) were originally developed to treat epilepsy. However, doctors often also prescribe them for nerve pain. Side effects may include drowsiness and dizziness.
• Lidocaine patch. This patch contains the topical anesthetic lidocaine. You apply it to the area where your pain is most severe, and you can use up to four patches a day to relieve pain. This treatment has almost no side effects except, for some people, a rash at the site of the patch.
• Antidepressants. Tricyclic antidepressant medications, such as amitriptyline and nortriptyline (Pamelor), were originally developed to treat depression. However, they have been found to help relieve pain by interfering with chemical processes in your brain and spinal cord that cause you to feel pain. The serotonin and norepinephrine reuptake inhibitor duloxetine (Cymbalta) also has proved effective for peripheral neuropathy caused by diabetes. Side effects may include nausea, drowsiness, dizziness, decreased appetite and constipation.
• Transcutaneous electrical nerve stimulation (TENS). In this therapy, adhesive electrodes are placed on the skin and a gentle electric current is delivered through the electrodes at varying frequencies. TENS has to be done frequently, but some people report this therapy improves their symptoms.

Prevention of Peripheral Neuropathy

Manage underlying conditions

The best way to prevent peripheral neuropathy is to carefully manage any medical condition that puts you at risk. That means controlling your blood sugar level if you have diabetes or talking to your doctor about safe and effective treatments if you think you may have a problem with alcohol.

Adopt healthy lifestyle habits

Whether or not you have a medical condition, eating healthy diet that's rich in fruits, vegetables, whole grains and lean protein can help keep your nerves healthy. For example, nerve damage is common if you have a vitamin B-12 deficiency. The best a food sources of vitamin B-12 are meats, fish, eggs, low-fat dairy foods and fortified cereals. If you're a strict vegetarian, fortified cereals are a good source of vitamin B-12 for you, but you may also want to talk to your doctor about B-12 supplements. Regular exercise also is important. If possible, try to get at least 30 minutes to one hour of exercise at least three times a week.

As much as possible, avoid things that can cause nerve damage, such as:

• Repetitive motions
• Cramped positions
• Toxic chemicals
• Tobacco smoke
• Excessive alcohol consumption

When to seek Medical Advice

Seek medical care right away if you notice any unusual tingling, weakness or pain in your hands or feet. Early diagnosis and treatment offers the best chance for controlling your symptoms and preventing further damage to your peripheral nerves. If your symptoms are interfering with your sleep or you feel depressed, your doctor or pain specialist may be able to suggest treatments that can help.