Peripheral Neuropathy: Symptoms, Causes, and How to Manage It

Peripheral neuropathy occurs when the nerves outside the brain and spinal cord become damaged, disrupting how signals travel throughout the body. These peripheral nerves play a vital role in carrying messages between the central nervous system and different body parts. As a result, when they are affected, communication breaks down, leading to noticeable symptoms. Most commonly, individuals experience weakness, numbness, or pain, especially in the hands and feet. However, the impact can extend beyond movement and sensation, influencing functions like digestion and urination as well.

This condition can develop due to several underlying factors, including injuries, infections, metabolic disorders, inherited conditions, or exposure to harmful toxins. Among these, diabetes remains one of the leading causes. People living with peripheral neuropathy often describe the discomfort as burning, stabbing, or tingling sensations. While symptoms may improve when the root cause is treated, management typically focuses on relieving pain and improving quality of life through appropriate care and medication.

Who Is at Risk of Peripheral Neuropathy?

Peripheral neuropathy can affect people of all ages, backgrounds, and lifestyles. It does not limit itself to a specific gender, race, or health profile. However, certain individuals may face a higher risk depending on the underlying conditions.

In addition, the likelihood of developing peripheral neuropathy increases with age. This is mainly because many age-related conditions, such as diabetes and other metabolic disorders, are closely linked to nerve damage. As a result, older adults are more commonly affected, which makes early awareness and proper management especially important.

How Common Is Peripheral Neuropathy?

Over 20 million Americans suffer from nerve damage in their extremities, a condition called peripheral neuropathy. For many, symptoms go beyond numbness and tingling, with over one-third experiencing sharp, prickling pain that can contribute to higher rates of depression. Some national studies estimate that about 13.5% of the U.S. population is affected by neuropathy.

Symptoms of Peripheral Neuropathy

Peripheral neuropathy can appear in many different ways because it may affect a single nerve, a group of connected nerves, or multiple nerves throughout the body. The symptoms a person experiences depend on which type of nerve is affected, such as motor, sensory, or autonomic, and sometimes more than one type can be involved at the same time.

Motor Symptoms

Motor nerves send signals from your brain to your muscles, allowing movement and coordination. When these nerves are damaged, muscles may not receive proper signals, leading to weakness and reduced control.

Common motor symptoms include:

• Muscle weakness: Difficulty lifting, walking, or holding objects
• Paralysis: In severe cases, limited or no movement in affected areas
• Foot drop: Trouble lifting the front part of the foot while walking
• Muscle atrophy: Gradual shrinking of muscles due to lack of nerve stimulation
• Cramps or twitching: Uncontrolled muscle movements caused by nerve misfiring

Sensory Symptoms

Sensory nerves carry information like touch, temperature, and pain to the brain. When these nerves are affected, the way you feel and interpret sensations can change or become unreliable.

Common sensory symptoms include:

• Tingling or “pins and needles”: A prickling sensation, often in hands or feet
• Numbness: Reduced or complete loss of sensation
• Burning or sharp pain: Often described as stabbing or electric-like pain
• Increased sensitivity: Even light touch may feel painful (allodynia)
• Poor balance or coordination: Difficulty staying steady, especially in low light

Autonomic Symptoms

Autonomic nerves control involuntary body functions such as digestion, heart rate, and temperature regulation. Damage to these nerves, known as autonomic neuropathy, can disrupt normal body processes without you being aware of it, such as in cases of diabetic autonomic neuropathy.

Common autonomic symptoms include:

• Blood pressure changes: Dizziness or lightheadedness when standing
• Abnormal sweating: Excessive sweating or inability to sweat properly
• Digestive issues: Constipation, diarrhea, or bloating
• Bladder problems: Difficulty controlling urination
• Sexual dysfunction: Changes in arousal or performance
• Vision or skin changes: Blurry vision, skin discoloration, or swelling

Causes of Peripheral Neuropathy

Peripheral neuropathy occurs when the peripheral nerves are damaged. This damage can result from a wide range of medical conditions, lifestyle factors, or external influences. Understanding the possible causes helps in prevention, early detection, and management.

Health Conditions:

• Autoimmune diseases: Conditions such as Sjogren’s syndrome, lupus, rheumatoid arthritis, Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy, and vasculitis can lead to nerve damage. Some cancers can trigger an autoimmune response called paraneoplastic syndrome, causing neuropathy.
• Diabetes and metabolic syndrome: These are the most common causes of peripheral neuropathy. Over half of people with diabetes develop some form of nerve damage.
• Tumors: Both malignant (cancerous) and benign (noncancerous) growths can press on or damage nerves.
• Inherited disorders: Genetic conditions such as Charcot-Marie-Tooth disease run in families and cause hereditary neuropathy.
• Infections: Certain viral or bacterial infections, including Lyme disease, shingles, hepatitis B and C, leprosy, diphtheria, and HIV, can affect peripheral nerves.
• Bone marrow disorders: Conditions such as monoclonal gammopathies, rare forms of myeloma, lymphoma, and amyloidosis can affect nerve function.
• Other diseases: Kidney or liver disease and hypothyroidism (underactive thyroid) may contribute to nerve damage.

Other Causes:

• Alcohol use disorder: Poor diet and vitamin deficiencies associated with alcoholism can harm nerve health.
• Medications: Certain drugs, particularly chemotherapy, can cause peripheral neuropathy.
• Exposure to toxins: Industrial chemicals and heavy metals like lead and mercury can damage nerves.
• Vitamin deficiencies: Low levels of B vitamins (B1, B6, B12), copper, and vitamin E can impair nerve function.
• Injury or nerve pressure: Accidents, falls, sports injuries, casts, crutches, or repetitive motions like typing can damage nerves.
• Idiopathic neuropathy: In some cases, the exact cause cannot be determined, which is referred to as idiopathic peripheral neuropathy.

Also read: Small Fiber Neuropathy: Symptoms, Causes, and Treatment

How Peripheral Neuropathy Is Diagnosed

Diagnosing peripheral neuropathy typically involves reviewing your medical history, performing a physical examination, and conducting specialized tests to confirm nerve damage and identify its cause.

When you visit a GP, they will first ask about your symptoms and examine the affected areas. This may include checking your sensation, muscle strength, and reflexes. Blood tests are often ordered to screen for common causes, such as diabetes or vitamin B12 deficiency.

In some cases, a referral to a neurologist may be necessary for more detailed testing. Common tests include:

• Nerve conduction study (NCS): Small electrodes are placed on the skin to send tiny electrical impulses through the nerves, measuring the speed and strength of nerve signals.
• Electromyography (EMG): A fine needle is inserted into the muscles to record their electrical activity. NCS and EMG are often performed together to provide a complete picture of nerve and muscle function.

To identify the underlying cause, your doctor may consider additional tests:

• Blood tests to detect rare acquired conditions or genetic disorders such as Charcot-Marie-Tooth disease
• A lumbar puncture to examine cerebrospinal fluid for signs of inflammation
• Imaging scans, including X-rays, CT scans, or MRI scans, to detect structural problems or tumors

In rare cases, a nerve biopsy may be performed. This minor surgical procedure removes a small sample of a peripheral nerve, usually near the ankle, to look for microscopic changes indicating neuropathy. However, nerve biopsies are not commonly required.

Read more: Is Peripheral Neuropathy a Disability? A Comprehensive Guide

Treatment of Peripheral Neuropathy

The main goals of treating peripheral neuropathy are to address the underlying cause and relieve symptoms. If tests do not reveal a specific cause, your healthcare provider may recommend watchful waiting to monitor whether symptoms remain stable, improve, or worsen over time.

Medicines

Several medications can help manage peripheral neuropathy, either by targeting the underlying condition or by reducing symptoms:

• Pain relievers: Over-the-counter medicines, such as nonsteroidal anti-inflammatory drugs (NSAIDs), can ease mild pain.
• Anti-seizure medicines: Drugs like gabapentin (Gralise, Neurontin, Horizant) and pregabalin (Lyrica), originally developed for epilepsy, are often effective for nerve pain. Side effects may include drowsiness and dizziness.
• Topical treatments: Lidocaine creams and patches can be applied to the skin to reduce localized pain. Possible side effects include numbness, drowsiness, or dizziness.
• Antidepressants: Certain tricyclic antidepressants, such as amitriptyline and nortriptyline (Pamelor), and serotonin-norepinephrine reuptake inhibitors like duloxetine (Cymbalta), venlafaxine (Effexor XR), and desvenlafaxine (Pristiq) may relieve nerve pain, including pain caused by diabetes. Side effects can include dry mouth, nausea, drowsiness, dizziness, changes in appetite, weight gain, and constipation.

Therapies and Procedures

In addition to medicines, a range of therapies and procedures can help manage symptoms:

• Scrambler therapy: Uses electrical impulses to send “non-pain” signals to the brain, retraining it to perceive less pain.
• Spinal cord stimulation: Neurostimulator devices implanted in the body send low-level electrical impulses to block pain signals from reaching the brain.
• Plasma exchange, steroids, and intravenous immune globulin: Often used when inflammation or autoimmune conditions cause neuropathy with weakness, numbness, or imbalance. These treatments do not target pain alone.
• Physical therapy: Helps improve mobility, strength, and balance. Braces, canes, walkers, or wheelchairs may be recommended for support.
• Surgery: May be needed if neuropathy is caused by pressure on nerves, such as from tumors or other structural problems.

The Importance of Clinical Trials in Neurology

Clinical trials are vital in neurology because they help researchers test new treatment possibilities, improve understanding of nerve disorders, and find safer, more effective ways to manage various neurological conditions. One example is ongoing distal sensory polyneuropathy clinical trials, which evaluates the safety and effectiveness of an investigational treatment for DSP-related nerve pain. By participating, individuals may gain access to a potential new treatment and get the opportunity to contribute to advancing neurological care.

Conclusion:

In conclusion, peripheral neuropathy affects the nerves outside the brain and spinal cord, causing symptoms like numbness, tingling, pain, and muscle weakness. Early diagnosis, treating the underlying causes, and proper management through medications, therapies, and lifestyle changes can reduce symptoms, improve quality of life, and help people live more comfortably with this condition.