Published: 18 Jun 2025

ICD9: 356.9      ICD10: G62.9      ICD11: 8D43.2Y

Peripheral neuropathy, often referred to as polyneuropathy when it affects multiple nerves, is a condition resulting from damage to the peripheral nerves.
These nerves are responsible for transmitting information between the brain and spinal cord and the rest of the body, including the skin, muscles, and internal organs. When these nerves are damaged, it can disrupt this communication, leading to a variety of symptoms.

Here's a breakdown of the key aspects:

What it is:

Peripheral Nerves: These are all the nerves outside of the brain and spinal cord. They form a vast network that relays sensory information (touch, pain, temperature) to the brain and carries motor signals from the brain to the muscles and glands.
Neuropathy: This simply means "nerve damage" or "nerve disease."
Polyneuropathy: This specifically means that many (multiple) peripheral nerves are affected. This is the most common form of peripheral neuropathy. If only a single nerve is affected, it's called mononeuropathy (e.g., carpal tunnel syndrome).

Causes:

Peripheral neuropathy has a wide range of potential causes. Some of the most common include:

Diabetes: This is the leading cause of peripheral neuropathy. High blood sugar levels can damage nerves over time.
Alcoholism: Excessive alcohol consumption can directly damage nerves and lead to nutritional deficiencies that contribute to nerve damage.
Vitamin Deficiencies: Deficiencies in certain vitamins, particularly B1 (thiamine), B12, B6, E, and niacin, can cause nerve damage.
Infections: Certain viral and bacterial infections, such as HIV, Lyme disease, shingles, hepatitis C, and leprosy, can damage nerves.
Autoimmune Diseases: Conditions like rheumatoid arthritis, lupus, Sjogren's syndrome, and Guillain-Barré syndrome can cause the immune system to attack the nerves.
Kidney Disease: Kidney failure can lead to a buildup of toxins in the body that can damage nerves.
Liver Disease: Similar to kidney disease, liver dysfunction can lead to toxic substances that affect nerves.
Exposure to Toxins: Certain chemicals, heavy metals (lead, mercury), and industrial solvents can cause nerve damage.
Medications: Some medications, including chemotherapy drugs, certain antibiotics, and heart medications, can have peripheral neuropathy as a side effect.
Inherited Disorders: Some genetic conditions, such as Charcot-Marie-Tooth disease, can cause peripheral neuropathy.
Trauma/Injury: Physical trauma, such as fractures or dislocations, can directly damage nerves.
Tumors: Tumors that grow near or on nerves can compress and damage them.
Idiopathic: In some cases, the cause of peripheral neuropathy cannot be identified. This is called idiopathic neuropathy.

Symptoms:

The symptoms of peripheral neuropathy vary depending on the type of nerves affected (sensory, motor, or autonomic) and the severity of the damage. Common symptoms include:

Numbness and Tingling: Often starts in the hands and feet and can spread up the limbs. This is often described as a "pins and needles" sensation.
Sharp, Throbbing, Freezing, or Burning Pain: This pain can be constant or intermittent. It's often worse at night.
Increased Sensitivity to Touch: Even light touch can be painful (allodynia).
Loss of Coordination: Difficulty with balance and walking.
Muscle Weakness: Especially in the feet and legs.
Loss of Reflexes: Particularly in the ankles.
Muscle Cramps:
Heat Intolerance:
Changes in Blood Pressure: Dizziness or lightheadedness upon standing (orthostatic hypotension).
Digestive Problems: Nausea, vomiting, diarrhea, or constipation.
Bladder or Bowel Control Problems:
Sexual Dysfunction:
Sweating Abnormalities: Excessive sweating or inability to sweat.

Diagnosis:

Diagnosing peripheral neuropathy involves a combination of:

Medical History and Physical Exam: The doctor will ask about your symptoms, medical history, and lifestyle.
Neurological Exam: The doctor will assess your reflexes, muscle strength, sensation, and coordination.
Nerve Conduction Studies (NCS): These tests measure the speed and strength of electrical signals traveling along nerves.
Electromyography (EMG): This test measures the electrical activity of muscles.
Blood Tests: To check for underlying conditions such as diabetes, vitamin deficiencies, kidney or liver disease, and autoimmune disorders.
Nerve Biopsy: In rare cases, a small sample of nerve tissue may be taken for examination under a microscope.
Imaging Tests: MRI or CT scans may be used to look for tumors or other abnormalities that could be compressing nerves.

Treatment:

Treatment for peripheral neuropathy focuses on:

Addressing the Underlying Cause: If the neuropathy is caused by an underlying condition like diabetes or vitamin deficiency, treating that condition is essential.
Pain Management:
Medications: Pain relievers (over-the-counter or prescription), antidepressants (such as duloxetine or amitriptyline), anti-seizure medications (such as gabapentin or pregabalin), and topical treatments (such as capsaicin cream) may be used to manage pain.
Physical Therapy: Exercises can help improve muscle strength, balance, and coordination.
Occupational Therapy: Can help you adapt to your limitations and find ways to perform daily tasks more easily.
Alternative Therapies: Acupuncture, massage, biofeedback, and transcutaneous electrical nerve stimulation (TENS) may provide some relief for some people.
Lifestyle Modifications:
Healthy Diet: Eating a balanced diet rich in fruits, vegetables, and whole grains can help improve overall health and nerve function.
Regular Exercise: Can help improve circulation and muscle strength.
Avoiding Alcohol and Smoking: These substances can damage nerves.
Foot Care: If you have neuropathy in your feet, it's important to inspect your feet daily for cuts, blisters, or other problems. Wear comfortable shoes and socks, and see a podiatrist regularly.

Prognosis:

The prognosis for peripheral neuropathy varies depending on the cause and severity of the condition. In some cases, the neuropathy can be reversed with treatment. In other cases, the neuropathy may be chronic and progressive, requiring ongoing management.

Important Considerations:

Early Diagnosis and Treatment: Early diagnosis and treatment are crucial for preventing further nerve damage and improving the chances of recovery.
Consult a Doctor: If you experience any symptoms of peripheral neuropathy, it's important to see a doctor for diagnosis and treatment.
Individualized Treatment Plan: Treatment plans should be tailored to the individual's specific needs and the underlying cause of the neuropathy.

In summary, peripheral neuropathy is a complex condition with many potential causes and a wide range of symptoms. Understanding the underlying cause is key to effective management. Prompt diagnosis and treatment are important to minimize nerve damage and improve quality of life.