Peripheral neuropathy, a result of damage to your peripheral nerves, often causes weakness, numbness and pain, usually in your hands and feet. It can also affect other areas of your body.

Your peripheral nervous system sends information from your brain and spinal cord (central nervous system) to the rest of your body. Peripheral neuropathy can result from traumatic injuries, infections, metabolic problems, inherited causes and exposure to toxins. One of the most common causes is diabetes mellitus.

People with peripheral neuropathy generally describe the pain as stabbing or burning. Often, there's tingling. In many cases, symptoms improve, especially if caused by a treatable underlying condition. Medications can reduce the pain of peripheral neuropathy.

Every nerve in your peripheral system has a specific function, so symptoms depend on the type of nerves affected. Nerves are classified into:

  • Sensory nerves that receive sensation from the skin such as temperature, pain, vibration or touch
  • Motor nerves that control how your muscles move
  • Autonomic nerves that control functions such as blood pressure, heart rate, digestion and bladder

Signs and symptoms of peripheral neuropathy may include:

  • Gradual onset of numbness and tingling in your feet or hands, which may spread upward into your legs and arms
  • Sharp, jabbing or burning pain
  • Extreme sensitivity to touch
  • Lack of coordination and falling
  • Muscle weakness or paralysis if motor nerves are affected

If autonomic nerves are affected, signs and symptoms may include:

  • Heat intolerance and altered sweating
  • Bowel, bladder or digestive problems
  • Changes in blood pressure, causing dizziness or lightheadedness

Peripheral neuropathy may affect one nerve (mononeuropathy), two or more nerves in different areas (multiple mononeuropathy) or many nerves (polyneuropathy).

When to see a doctor

Seek medical care right away if you notice unusual tingling, weakness or pain in your hands or feet. Early diagnosis and treatment offer the best chance for controlling your symptoms and preventing further damage to your peripheral nerves.

A number of factors can cause neuropathies, including:

  • Alcoholism. Poor dietary choices made by alcoholics can lead to vitamin deficiencies.
  • Autoimmune diseases. These include Sjogren's syndrome, lupus, rheumatoid arthritis, Guillain-Barre syndrome, chronic inflammatory demyelinating polyneuropathy and necrotizing vasculitis.
  • Diabetes. More than half of people with diabetes develop some type of neuropathy.
  • Exposure to poisons. Toxic substances include heavy metals or chemicals.
  • Medications. Certain medications, especially those used to treat cancer (chemotherapy), may cause peripheral neuropathy.
  • Infections. These include certain viral or bacterial infections, including Lyme disease, shingles (varicella-zoster), Epstein-Barr virus, hepatitis C, leprosy, diphtheria and HIV.
  • Inherited disorders. Disorders such as Charcot-Marie-Tooth disease are hereditary types of neuropathy.
  • 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 having a cast or using crutches or repeating a motion many times, such as typing.
  • Tumors. Growths, cancerous (malignant) and noncancerous (benign), can develop on the nerves themselves or they can put pressure on surrounding nerves.
  • Vitamin deficiencies. B vitamins, including B-1, B-6 and B-12, vitamin E and niacin are crucial to nerve health.
  • Bone marrow disorders. These include abnormal protein in the blood (monoclonal gammopathies), a form of bone cancer (osteosclerotic myeloma), lymphoma and amyloidosis.
  • Other diseases. These include kidney disease, liver disease, connective tissue disorders and an underactive thyroid (hypothyroidism).

Peripheral neuropathy risk factors include:

  • Diabetes mellitus, especially if your sugar levels are poorly controlled
  • Alcohol abuse
  • Vitamin deficiencies, particularly B vitamins
  • Infections, such as Lyme disease, shingles (varicella-zoster), Epstein-Barr virus, hepatitis C and HIV
  • Autoimmune diseases, such as rheumatoid arthritis and lupus, in which your immune system attacks your own tissues
  • Kidney, liver or thyroid disorders
  • Exposure to toxins
  • Repetitive motion, such as those performed for certain jobs
  • Family history of neuropathy

Complications of peripheral neuropathy may include:

  • Burns and skin trauma. If parts of your body are numb, you may not feel temperature changes or pain.
  • Infection. Your feet and other areas lacking sensation can become injured without your knowing. Check these areas regularly and treat minor injuries before they become infected, especially if you have diabetes mellitus.

You're likely to start by seeing your family doctor or a general practitioner. You may then be referred to a doctor trained in nervous system disorders (neurologist).

Here's information to help you prepare for your appointment.

What you can do

  • Write down your symptoms, including any that may seem unrelated to your reason for scheduling the appointment.
  • List medications, vitamins and supplements you're taking.
  • Ask a family member or friend to accompany you. A companion may remember something you missed.
  • Write down questions for your doctor.

Preparing a list of questions can help you make the most of your time with your doctor. For peripheral neuropathy, some basic questions include:

  • What's the most likely cause of my symptoms?
  • Are there other possible causes?
  • What tests do I need? Do these tests require any special preparation?
  • Is this condition temporary or long lasting?
  • What treatments are available, and which do you recommend?
  • What side effects can I expect from treatment?
  • Are there alternatives to the primary approach you're suggesting?
  • I have other health conditions. How can I best manage them together?
  • Do I need to restrict activities?
  • Is there a generic alternative to the medicine you're prescribing?
  • Are there brochures or other printed material I can take? What websites do you recommend?

Don't hesitate to ask other questions.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, such as:

  • Do you have underlying health conditions, such as diabetes or kidney disease?
  • When did your symptoms begin?
  • Have your symptoms been continuous or occasional?
  • How severe are your symptoms?
  • Does anything seem to improve your symptoms?
  • What, if anything, appears to worsen your symptoms?
  • Does anyone in your family have symptoms similar to yours?

Peripheral neuropathy isn't a single disease, but rather damage to nerves that produces symptoms with many potential causes. Your doctor will need to determine where the nerve damage is and what's causing it.

Besides a physical exam, which may include blood tests, diagnosis usually requires:

  • A full medical history. Your doctor will review your medical history, including your symptoms, your lifestyle, exposure to toxins, drinking habits and a family history of nervous system (neurological) diseases.
  • Neurological examination. Your doctor may check your tendon reflexes, your muscle strength and tone, your ability to feel certain sensations, and your posture and coordination.

Your doctor may order tests, including:

  • Imaging tests. CT or MRI scans can look for herniated disks, tumors or other abnormalities.
  • Nerve function tests. Electromyography, a nerve function test, records electrical activity in your muscles to determine if your symptoms, including weakness, are caused by muscle or nerve damage.

    For nerve conduction studies, a probe sends electrical signals to a nerve, and an electrode placed along the nerve's pathway records the nerve's response to the signals. Nerve conduction studies record signals from both motor and sensory nerves.

  • Other nerve function tests. These may include an autonomic reflex screen that records how the autonomic nerve fibers work, a sweat test that records how you sweat, and sensory tests that record how you feel touch, vibration, cooling and heat.
  • Nerve biopsy. Your doctor may recommend removing a small portion of a nerve, usually a sensory nerve, to examine for abnormalities to determine the cause of your nerve damage.
  • Skin biopsy. Your doctor removes a small portion of skin to examine the number of nerve endings. A reduction in nerve endings indicates neuropathy.

Treatment goals are to manage the condition causing your neuropathy and to relieve symptoms. If your lab tests indicate no underlying condition, your doctor may recommend watchful waiting to see if your neuropathy improves. If exposure to toxins or alcohol is causing your conditions, your doctor will recommend avoiding those substances.

Medications

Medications used to relieve peripheral neuropathy pain include:

  • Pain relievers. Over-the-counter pain medications, such as nonsteroidal anti-inflammatory drugs, can relieve mild symptoms. For more-severe symptoms, your doctor may recommend prescription painkillers.

    Medications containing opioids, such as tramadol (Conzip, Ultram ER, others) or oxycodone (Oxycontin, Roxicodone, others), can lead to dependence and addiction, so these drugs generally are prescribed only when other treatments fail.

  • Anti-seizure medications. Medications such as gabapentin (Gralise, Neurontin) and pregabalin (Lyrica), developed to treat epilepsy, may relieve nerve pain. Side effects may include drowsiness and dizziness.
  • Capsaicin. A cream containing this substance found naturally in hot peppers can cause modest improvements in peripheral neuropathy symptoms. Doctors may suggest you use this cream with other treatments. Skin burning and irritation where you apply the cream may occur, but usually lessens over time. However, some people can't tolerate it.
  • Antidepressants. Certain tricyclic antidepressants, such as amitriptyline, doxepin and nortriptyline (Pamelor), 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) and the extended-release antidepressant venlafaxine (Effexor XR) also may ease the pain of peripheral neuropathy caused by diabetes. Side effects may include dry mouth, nausea, drowsiness, dizziness, decreased appetite and constipation.

Your doctor also may prescribe medication to treat the underlying condition that's causing the neuropathy. For example, medications to reduce your immune system's reaction, such as prednisone, cyclosporine (Neoral, Sandimmune, others), mycophenolate mofetil (CellCept) and azathioprine (Azasan, Imuran), may help people with peripheral neuropathy associated with autoimmune conditions.

Intravenous immunoglobulin is a mainstay of treatment for chronic inflammatory demyelinating polyneuropathy and other inflammatory neuropathy.

Therapies

Various therapies and procedures may help ease the signs and symptoms of peripheral neuropathy.

  • Transcutaneous electrical nerve stimulation (TENS). Adhesive electrodes placed on the skin deliver a gentle electric current at varying frequencies. TENS should be applied for 30 minutes daily for about a month.
  • Plasma exchange and intravenous immune globulin. People with certain inflammatory conditions may benefit from these procedures, which help suppress immune system activity.

    Plasma exchange involves removing your blood, then removing antibodies and other proteins from the blood and returning the blood to your body. In immune globulin therapy, you receive high levels of proteins that work as antibodies (immunoglobulins).

  • Physical therapy. If you have muscle weakness, physical therapy can help improve your movements. You may also need hand or foot braces, a cane, a walker, or a wheelchair.
  • Surgery. If you have neuropathies caused by pressure on nerves, such as pressure from tumors, you may need surgery to reduce the pressure.

Here are suggestions to help you manage peripheral neuropathy:

  • Take care of your feet, especially if you have diabetes. Check daily for blisters, cuts or calluses. Wear soft, loose cotton socks and padded shoes. You can use a semicircular hoop, which is available in medical supply stores, to keep bedcovers off hot or sensitive feet.
  • Exercise. Ask your doctor about an exercise routine. Regular exercise, such as walking three times a week, may reduce neuropathy pain, improve your muscle strength and help control blood sugar levels. Gentle routines such as yoga and tai chi might also help.
  • Quit smoking. Cigarette smoking can affect circulation, increasing the risk of foot problems and other neuropathy complications.
  • Eat healthy meals. Healthy eating is especially important to ensure that you get essential vitamins and minerals. Emphasize low-fat meats and dairy products and include lots of fruits, vegetables and whole grains in your diet.
  • Avoid excessive alcohol. Alcohol may worsen peripheral neuropathy.
  • Monitor your blood glucose levels. If you have diabetes, monitoring your blood glucose levels will help keep your blood glucose under control and may help improve your neuropathy.

Some people with peripheral neuropathy try complementary and alternative treatments for relief of their symptoms. Although researchers haven't studied these techniques as thoroughly as they have most medications, the following therapies have shown some promise:

  • Acupuncture. Acupuncture, which involves inserting thin needles into various points on your body, may reduce peripheral neuropathy symptoms. You may need multiple sessions before you notice improvement. Acupuncture is generally considered safe when performed by a certified practitioner using sterile needles.
  • Alpha-lipoic acid. Used as a treatment for peripheral neuropathy in Europe for years, this antioxidant may help reduce symptoms. Discuss using alpha-lipoic acid with your doctor because it may affect blood sugar levels. Other side effects may include stomach upset and skin rash.
  • Herbs. Certain herbs, such as evening primrose oil, may help reduce neuropathy pain in people with diabetes. Some herbs interact with medications, so discuss herbs you're considering with your doctor.
  • Amino acids. Amino acids, such as acetyl-L-carnitine, may help improve peripheral neuropathy in people who have undergone chemotherapy and in people with diabetes. Side effects may include nausea and vomiting.
  • Fish oil. These supplements, which have omega-3 fatty acids, may reduce inflammation, improve blood flow and improve neuropathy symptoms in people with diabetes. Check with your doctor before taking fish oil supplements if you're taking anti-clotting medications.

Manage underlying conditions

The best way to prevent peripheral neuropathy is to manage medical condition that put you at risk, such as diabetes, alcoholism or rheumatoid arthritis.

Make healthy lifestyle choices

For example:

  • Eat a diet rich in fruits, vegetables, whole grains and lean protein to keep nerves healthy. Protect against vitamin B-12 deficiency by eating meats, fish, eggs, low-fat dairy foods and fortified cereals. If you're vegetarian or vegan, fortified cereals are a good source of vitamin B-12, but also talk to your doctor about B-12 supplements.
  • Exercise regularly. With your doctor's okay, try to get at least 30 minutes to one hour of exercise at least three times a week.
  • Avoid factors that may cause nerve damage, including repetitive motions, cramped positions, exposure to toxic chemicals, smoking and overindulging in alcohol.
Dec. 02, 2014