Peripheral neuropathy is a medical condition in which the nerves passing signals of physical sensation to the brain do not work properly. The condition arises when the peripheral nerves are either damaged or destroyed. This leads to an alteration in the normal functioning of the nerve. Due to the damage, the brain either does not receive signals or may receive the wrong signal. For example, the brain may not get a pain signal when something is hurting. Ot it may receive pain signals when there is nothing that leads to pain.   

The reasons attributed to the condition are:

• Infection
  
• Injury
  
• Inherited disorder
  
• Systemic illness.
  

Symptoms of peripheral neuropathy

The common symptoms observed in peripheral neuropathy patients are:

• Loss of balance and coordination
  
• Weakness in muscle mainly in the feet
  
• Tingling sensation and numbness in the hands and feet
  
• Intense pain in the afflicted area.
  

Causes

• The most important cause of peripheral neuropathy is diabetes, both type 1 or type 2. It is known that higher levels of sugar in the blood can cause serious damage to nerves. When neuropathy (damage of nerves) is caused by high blood sugar levels then it is known as diabetic polyneuropathy or diabetic neuropathy.
  
• It can be due to shingles (virus infection).
  
• Physical nerve injury.
  
• Excessive alcohol consumption.
  
• A side-effect of some medicines
  
• Inherited disease such as Charcot-Marie-Tooth disease
  
• Bacterial or viral infections like HIV, Epstein-Barr virus, Lyme disease, hepatitis B and C, diphtheria, and leprosy.
  

Risk factors

The risk factors are:

• Excessive consumption of alcohol
  
• Deficiency of vitamins, mainly vitamin B
  
• Patient with diabetes
  
• Different infections like shingles, hepatitis B and C, Epstein-Barr virus, HIV, Lyme disease
  
• Autoimmune disease such as rheumatoid arthritis.
  
• Direct contact with toxins
  
• Repetitive motion
  
• Disorders of kidney, thyroid, and liver
  
• Family history
  

Complications

The main complications of peripheral neuropathy are:

• The trauma of skin and burns: Due to the damage of nerves, the patient does not feel the pain or change in the temperature in the affected area. The damage in nerves makes the area numb.
  
• Infection: Due to the lack of sensation, the patient might not feel the injury when it is caused. They are left untreated and that leads to infection. If the patient is diabetic, he or she should check the areas daily.
  
• Balancing issue: Patient lacks balance and may fall due to sensation loss and weakness.
  

Diagnosis

Diagnosis of the diseases includes a physical examination and tests. 

Medical history

Many cases of neuropathies include patients having a medical history. The history of the patient is reviewed by the specialist to check the exposure to toxins, symptoms, lifestyle, any medical history of nervous system disorders in the family.

Neurological examination

This checks the strength of muscle, its tone, tendon reflexes, posture, coordination, and sensation.

Tests

• Blood test: This evaluates deficiencies, abnormal immune function, and diabetes. These are the problems that lead to peripheral neuropathy.
  
• Imaging tests like MRI and CT
  
• Nerve function test: It is done to check the electrical activity in the nerves.
  
• Nerve and skin biopsy.
  

Treatment

In in case of no underlying condition the patient is monitored for some time to observe the improvement in neuropathy. The doctor will opt for the treatment option if the diagnostic test reveals the primary condition. 

Medications

Some types of medications prescribed to provide relief in the symptoms are – 

• Pain reliever for acute pain like over-the-counter medication like NSAIDs (non-steroidal anti-inflammatory drugs).
  

• An opioid like Oxycodone and Roxicodone are used to treat neuropath. Usually they are prescribed in exceptional cases where all other treatment fails. This is because they cause addiction and drug dependence.
  

• Anti-epileptic drugs, like gabapentin and pregabalin,  treat seizures and reduce the nerve pain. They have side effects like dizziness.
  

• Topical medications like creams are successful in improving the symptoms of peripheral neuropathy. A person may experience prickling or irritation during the application of the cream. This may be unbearable but usually reside with time.
  

• To provide relief in pain, lidocaine patches are also available in the market. These may cause some numbness at the site of the patch and sleepiness.
  

• Antidepressants like amitriptyline and nortriptyline are also used to relieve pain. These drugs reduce the pain by altering the chemical process that results in pain in the brain and spinal cord.
  

• Other treatment options to reduce the pain are duloxetine (serotonin and norepinephrine reuptake inhibitor) and venlafaxine. These drugs mainly reduce the pain of neuropathy due to diabetes.
  

Therapies

Many therapies are used to retard or ease the peripheral neuropathy sign and symptoms. 

• TENS (Transcutaneous electrical nerve stimulation): Different frequency electric currents (mild) are produced by electrodes on the skin. The therapy is taken for a month with a daily application of half an hour.
• Plasma exchange and intravenous immune globulin: This helps in inflammatory problems by inhibiting the immune system.
• Physical therapy: It helps to enhance the movements of the body.
• Surgery: Biopsies of nerves to make a diagnosis or in case of compressive neuropathies such as carpal tunnel syndrome.

Prevention

• Choose a healthy lifestyle: Always eat the food which is good for nerves. This includes whole grains, vegetables, lean proteins, fruits, eggs, meats, low-fat dairy foods, fish, and fortified cereals. Doctors may recommend vitamin B-12 supplements also.
  
• Daily exercise: Individuals should exercise three times a week for about thirty minutes to one hour.
  
• Management of problems that can cause peripheral neuropathy like rheumatoid arthritis, diabetes, alcoholism.
  
• Avoid exposure to hazardous chemicals, stop smoking and drinking alcohol
  
• Reduce repetitive motions
  
• Change to different position while sitting to reduce the pressure on nerves.
  

Research

• A recent report presented at the virtual scientific sessions of the American Diabetes Association, based on a study known as SENZA-PDN, suggests that high-frequency spinal cord stimulation appears to be a promising and effective treatment for the pain associated with diabetic neuropathy.
  
• US FDA approved a new capsaicin drug for treating diabetic peripheral neuropathy (DPN) of the feet in July 2020
  

Frequently asked questions

What are the common symptoms of peripheral neuropathy?

Symptoms depend on the type and the cause of neuropathy. Therefore patients may have different symptoms depending on the underlying cause of disease. The main symptoms are numbness, piercing pain, muscle cramps, tingling sensation in feet, and the loss of control of movements in feet and hands.

Why do my symptoms of pain come and go?

The symptoms appear and disappear in the case of progressive polyneuropathy. 

How is neuropathic pain treated?

Doctors prescribe the medicine according to the need. It might be topical or oral medications. Vitamins supplements, hormones, pain relievers with anti-depressants are different options to treat neuropathic pain.

How can I manage burning sensations in my feet and legs?

Consult the doctor and they may prescribe topical cream or lidocaine patches to relieve the pain.