About peripheral neuropathy
What is peripheral neuropathy?
Peripheral neuropathy is disorder of nerve(s) apart from the brain and spinal cord. Patients with peripheral neuropathy may have tingling, numbness, unusual sensations, weakness, or burning pain in the affected area. Oftentimes, the symptoms are symmetrical and involve both hands and feet. Because the symptoms are often present in the areas covered by gloves or stockings, peripheral neuropathy is often described as having a “glove and stocking” distribution of symptoms.
Peripheral neuropathy can involve different nerve types, including motor, sensory, and autonomic nerves. Peripheral neuropathy can also be categorized by the size of the nerve fibers involved, large or small.
Neuropathy can present with many differing symptoms, including numbness, pain of different types, weakness, or loss of balance, depending on the type of nerve involved. Because the autonomic nerves control bodily functions that we do not consciously think of, such as heart rate, digestion, and emptying of the bowel and bladder, autonomic neuropathy manifests with symptoms affecting the loss of control of these functions. Symptoms may include problems with blood pressure, voiding, passage of stools (diarrhea, or constipation), heart rate, or sweating.
Cranial neuropathy is similar to peripheral neuropathy, except that the cranial nerves are involved. Any of the cranial nerves can be involved. One of the more common causes of cranial neuropathy is loss of blood flow from the optic artery to the optic nerve, causing ischemic optic neuropathy. Amyloidosis is one of the more common causes of this rare disorder.
Specific nerves can be involved in neuropathy. When a specific nerve is involved, the symptoms are limited to the distribution of that nerve. The most commonly involved peripheral nerve is the median nerve at the wrist in carpal tunnel syndrome. Essentially any peripheral nerve can become entrapped and cause the signs and symptoms of neuropathy. The ulnar nerve is commonly entrapped at the elbow. The peroneal nerve is exposed at the outer part of the knee. The pudendal nerve can cause pain in the perineum and is relieved by sitting on a toilet seat or an inflatable donut. Entrapment of the lateral femoral cutaneous nerve at the waist, called meralgia paresthetica, causes numbness at the outer part of the thigh.
What are the symptoms for 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, such as temperature, pain, vibration or touch, from the skin
- Motor nerves that control muscle movement
- Autonomic nerves that control functions such as blood pressure, heart rate, digestion and bladder
Signs and symptoms of peripheral neuropathy might include:
- Gradual onset of numbness, prickling or tingling in your feet or hands, which can spread upward into your legs and arms
- Sharp, jabbing, throbbing, freezing 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 might include:
- Heat intolerance and altered sweating
- Bowel, bladder or digestive problems
- Changes in blood pressure, causing Dizziness or lightheadedness
Peripheral neuropathy can affect one nerve (mononeuropathy), two or more nerves in different areas (multiple mononeuropathy) or many nerves (polyneuropathy). Carpal tunnel syndrome is an example of mononeuropathy. Most people with peripheral neuropathy have 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.
What are the causes for peripheral neuropathy?
Not a single disease, peripheral neuropathy is nerve damage caused by a number of conditions. Causes of neuropathies include:
- Alcoholism. Poor dietary choices made by people with alcoholism 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 the 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), can cause peripheral neuropathy.
- Infections. These include certain viral or bacterial infections, including Lyme disease, shingles, 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 from 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 such as typing many times.
- Tumors. Growths, cancerous (malignant) and noncancerous (benign), can develop on the nerves or press nerves. Also, polyneuropathy can arise as a result of some cancers related to the body's immune response. These are a form of paraneoplastic syndrome.
- 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).
In a number of cases, no cause can be identified (idiopathic).
What are the treatments for peripheral neuropathy?
The treatment for peripheral neuropathy depends on its cause. The first step in treatment is, therefore, to look for the cause.
- Vitamin deficiencies can be corrected.
- Diabetes can be controlled, although control may not reverse the neuropathy. The goal with diabetes is early detection and adequate treatment to prevent the occurrence of neuropathy.
- Neuropathies that are associated with immune diseases can improve with treatment of the autoimmune disease.
- Neuropathy caused by nerve entrapment can be treated by physical therapy, injections, or surgery.
- Prompt treatment with sympathetic injections can minimize the chance of shingles progressing to postherpetic neuralgia.
If a specific treatment isn't available, the pain of the neuropathy can usually be controlled with medications. The simplest treatment is over-the-counter (OTC) medications, such as acetaminophen, ibuprofen, or aspirin. Tricyclic antidepressants such as amitriptyline (Elavil) or nortriptyline (Pamelor) and antiseizure medications, such as carbamazepine (Tegretol) have been used to relieve the pain of neuropathy. Capsaicin, the chemical responsible for chili peppers being hot, is available over-the-counter as a cream to help relieve the pain of a peripheral neuropathy. A prescription patch of 8% capsaicin (Qutenza) is approved for the treatment of postherpetic neuralgia. Pregabalin (Lyrica) is a medication that is used for the treatment of postherpetic neuralgia and diabetic peripheral neuropathy, while duloxetine (Cymbalta) has been approved for use in the treatment of diabetic peripheral neuropathy. In some instances, opioids can be used to help control the pain that can be associated with peripheral neuropathy.
Both Vitamin B6 and alpha-lipoic acid have been used for relief in chemotherapy-induced peripheral neuropathy.
There is ongoing research into treatments for peripheral neuropathy, ranging from evaluating the effectiveness of topical gels to bone marrow treatments. As this research progresses, new therapies will become available.
A person who believes that he or she has peripheral neuropathy should contact their healthcare professional since many causes of peripheral neuropathy can be successfully treated.
What are the risk factors for peripheral neuropathy?
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, 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
Is there a cure/medications for peripheral neuropathy?
If your neuropathy is due to an underlying, treatable condition, you may be able to stop your peripheral neuropathy by treating the larger problem.
However, if this isn’t the case for you, you can successfully manage the symptoms of your peripheral neuropathy. Speak with your doctor to determine the best medical treatment for you, and explore complementary and self-care options that can supplement your medical care.