Peripheral neuropathy is a symptom rather than a disease in itself. It occurs when nerves are damaged resulting in pain and loss of function, such as motor movement or the sense of touch. Peripheral neuropathy commonly develops in the longest nerves first, affecting the toes and feet. Correcting the underlying cause of peripheral neuropathy, such as managing diabetes, can help resolve symptoms. Physical or occupational therapy, medications, and lifestyle changes may be recommended as well.
Your brain and the rest of the nervous system constantly exchange messages about your body. Certain nerve pathways have specific tasks. The motor nerves transmit signals about muscle movements. The sensory nerves send signals about what you feel, such as heat, cold, pain, and touch. Such functions as blood pressure, heart rate, digestion, and body temperature are automatic and controlled by the autonomic nervous system.
Peripheral neuropathy typically begins in the ends of the longest nerves, such as the sensory nerves in the toes and feet. However, peripheral neuropathy can affect other nervous systems, and the symptoms will depend on what functions the nerves control. For example, if the autonomic nervous system is involved, bowel and bladder problems may be present.
Peripheral neuropathy is caused by damage to one or several nerves. There are many causes of nerve damage, and a primary cause is diabetes (diabetic neuropathy). Other causes include trauma, disease, infection, alcoholism, vitamin deficiencies, chemotherapy, and toxins.
The symptoms of peripheral neuropathy are directly related to the affected nerve and the functions of that nerve. Peripheral neuropathy most frequently develops first in the longest nerves, such as those in the toes and feet, before the hands and arms. You may experience numbness and tingling that travels up the legs or arms. You may feel burning pain or extremely sharp pain. The slightest touch may feel extremely sensitive. You may lose sensation causing numbness. Movements may be weak, paralyzed, or uncoordinated.
If peripheral neuropathy progresses to the autonomic nerves that control organs, it can change bowel and bladder functions. It may also affect breathing, swallowing, digestion, and vision. It can cause impotence in men. Fainting or dizziness can occur if blood pressure is affected.
As peripheral neuropathy is a symptom, your doctor will evaluate you to determine its cause. Your doctor will review your medical history and examine you. Blood tests may be used to screen for underlying medical conditions, such as diabetes, thyroid disease, or vitamin deficiencies.
Your examination will include a clinical neurological exam, which includes reflex and sensation testing. Electromyography (EMG) and nerve conduction studies may be used to assess the speed and strength of nerve signals to certain muscles. A nerve biopsy may be used to identify abnormalities. In some cases, imaging scans may be used to help determine if there is pressure on a nerve.
There are many ways to treat and manage peripheral neuropathy. The treatment that you receive depends on many factors, such as its severity, underlying cause, and the nerves that are involved. For some people, treatment of the underlying cause results in improvement of symptoms.
Several types of medications or combinations of medications may be recommended. Over-the-counter or prescription pain relievers, anti-seizure medications, antidepressants, and local anesthetic patches may be prescribed.
Physical and occupational therapy may help improve muscle strength, coordination, and range of motion. Your therapists may recommend braces or splints to position your joints. Ambulation devices, such as a walker, cane, or crutches can increase mobility. Your therapists may use transcutaneous electrical nerve stimulation (TENS) to deliver a small electrical current to nerves to relieve pain. A home evaluation performed by your therapists can ensure that your living space is as safe as possible.
Lifestyle changes can help peripheral neuropathy. Examine your feet regularly and report any changes to your doctor. He can recommend the best types of shoes for you. Exercise regularly, quit smoking, avoid alcohol, and eat healthy balanced meals. Your doctor can make specific recommendations for you.
You may prevent complications from peripheral neuropathy by managing its underlying cause. Follow your doctor’s advice and attend all of your appointments. Bring any new changes to your doctor’s attention promptly.
Am I at Risk?
Risk factors for peripheral neuropathy:
- Pressure from nerve compression
- Diseases, such as diabetes, cancer, thyroid disease, or kidney failure
- Infections, such as HIV/AIDS, rheumatoid arthritis, or hepatitis
- Vitamin B deficiency
- Exposure to toxins or poisons
Decreased sensation and coordination in the feet or toes increases the risk of falls. Your therapists can work with you on a fall prevention program.