What to know about polyneuropathy

Peripheral nerves are nerves located outside the brain and spinal cord. They relay information between the central nervous system (CNS) and all other parts of the body. The brain and spinal cord are part of the CNS.

Polyneuropathy affects several nerves in different parts of the body at the same time. In cases of mononeuropathy, just one nerve is affected.

Polyneuropathy can affect nerves responsible for:

• feeling (sensory neuropathy)
• movement (motor neuropathyTrusted Source)
• both feeling and movement (sensorimotor neuropathy)

It may also affect the autonomic nervesTrusted Source responsible for controlling functions such as digestion, the bladder, blood pressure, and heart rate.

Although the exact number of people with polyneuropathy is not known, between 1% and 7% of people in the United States have peripheral neuropathy. Among people older than 50 years, these rates are on the higher end.

There are more than 100Trusted Source types of peripheral neuropathy, most of which are polyneuropathies.

Each type is classified according to the type of nerve damage, the underlying cause, and the symptoms it produces.

For example, diabetic neuropathy occurs in people with diabetes, whereas idiopathic neuropathy appears to have no known cause.

There are three main patterns of polyneuropathy:

• Chronic symmetrical peripheral neuropathy: Most polyneuropathies are chronic and develop over many months.
• Multiple mononeuropathy: There is damage to at least two separate nerve areas.
• Acute symmetrical peripheral neuropathy: This is rare. The most common cause is Guillain-Barré syndrome, a condition that can be fatal.

Some neuropathies can take years to develop, but others become severe within hours to days of onset.

Several medical conditions and other factors can cause polyneuropathy, includingTrusted Source:

• Diabetes: This can be a significant risk factor, especially if blood sugar levels are difficult to manage. A 2023 study of 25,710 people in China with type 2 diabetes found that 20% to 80% had had diabetic peripheral neuropathy with some variations according to geographical location.
• Alcohol misuse: Alcohol can damage nerve tissue, and alcohol use disorder is often associated with nutritional deficiencies that contribute to neuropathy.
• Autoimmune conditions: The immune system attacks the body, causing damage to nerves and other areas. Conditions include Sjogren disease, celiac disease, Guillain-Barré syndrome, rheumatoid arthritis, and lupus.
• Bacterial or viral infections: Certain infections, including Lyme disease, shingles, hepatitis B, hepatitis C, and HIV, can lead to neuropathy.
• Bone marrow disorders: Examples of these include abnormal proteins in the blood, some forms of bone cancer, and lymphoma.
• Exposure to toxins: Toxic neuropathy may be due to exposure to industrial chemicals such as arsenic, lead, mercury, and thallium. Drug or chemical misuse is also a risk factor.
• Hereditary disorders: Certain conditions, such as Charcot-Marie-Tooth disease, are forms of hereditary neuropathy.
• Hypothyroidism: An underactive thyroid may lead to polyneuropathy, although this is uncommon.
• Kidney disease: Uremic neuropathy is a form of polyneuropathy affecting 60% to 70% of people with chronic kidney disease.
• Liver disease: Research from 2018 indicates that peripheral neuropathy is very common in those with cirrhosis of the liver.
• Medications: Drugs that can cause neuropathy include chemotherapy and some drugs to treat HIV or stage 3 HIV.
• Difficulty eating a balanced diet: Deficiencies of vitamins B1, B12Trusted Source, and vitamin E, as well as an elevated (toxic) level of B6Trusted Source, may lead to polyneuropathy. These vitamins are vital for nerve health.
• Physical trauma or injury: Repetitive motion such as typing, accidents, or other injuries can damage peripheral nerves.

Some cases of polyneuropathy have no known cause. These are known as idiopathic neuropathy.

Polyneuropathy can produce a variety of symptoms, depending on which nerves are affected.

Symptoms associated with sensory or motor nerve damage can includeTrusted Source:

• tingling
• numbness
• pins and needles
• difficulty using the arms, legs, hands, or feet
• increased pain (such as burning, stabbing, freezing, or shooting pains)
• sleep problemsTrusted Source due to night-time pain
• inability to feel painTrusted Source
• extreme sensitivity to touch
• inability to sense temperature changes
• lack of coordination
• increased episodes of falling
• foot and leg ulcers
• skin and nail infections
• muscle weakness
• muscle twitching

Symptoms associated with autonomic nerve damage include:

• heat intolerance
• unusual sweating
• bladder problems or incontinence
• digestive problems
• dizziness
• blood pressure or pulse irregularities
• difficulty eating or swallowing
• difficulty breathing
• inability to sense temperature changes
• lack of coordination

Other conditions with similar symptoms

Fibromyalgia and polyneuropathy may have similar symptoms, but the cause of fibromyalgia is unknown.

Similarities also exist between multiple sclerosis and peripheral neuropathy.

Conditions associated with polyneuropathy

There are many conditions associated with polyneuropathy, including:

• amyloidosisTrusted Source
• celiac disease
• Charcot-Marie-Tooth Disease
• diabetes
• diphtheria
• Guillain-Barré Syndrome
• hepatitis B
• hepatitis C
• HIV
• stage 3 HIV
• kidney disease
• hypothyroidism
• Hansen’s disease (leprosy)
• liver disease
• Lyme disease
• lymphoma
• osteosclerotic myeloma
• pernicious anemia (vitamin B12 deficiency)
• radiculopathyTrusted Source
• rheumatoid arthritis
• shingles
• Sjogren disease

Complications

Common complications associated with polyneuropathy include:

• Falls and injury: A lack of balance and coordination, along with muscle weakness, can lead to an increase in falls and injuries sustained from falls.
• Burns and skin damage: Numbness and an inability to feel pain or temperature changes can lead to accidental burns, cuts, and other skin damage.
• Infections: Injuries, burns, and cuts, particularly on the legs and feet, can go unnoticed, leading to an increased risk of infection.

A polyneuropathy diagnosis considers a person’s medical history alongside a physical exam and neurological evaluation. Depending on the person’s symptoms, a doctor may order tests.

The doctor will take a detailed review of all symptoms, lifestyle factors, and family history.

They will also check the person’s height, weight, pulse, blood pressure, and temperature. They may also check the heart, lungs, and abdomen to help rule out alternative physiological causes.

Blood tests may be necessary to check for diabetes, thyroid function, immune function, nutrient deficiencies, and other factors that may cause polyneuropathy.

A doctor may also perform some simple tests to check reflexes, muscle strength, sensitivity to temperature and other sensations, coordination, and posture.

Other tests

Other tests that doctors may use in the diagnosis of polyneuropathy include:

• MRI or CT scan: These imaging techniques look for tumors, herniated disks, or other irregularities that may be affecting nerve function.
• Electro-diagnostic tests: These noninvasive tests measure the electrical activity in the muscles and nerves, helping detect nerve damage. Examples are electromyography and nerve conduction studies.
• Biopsies: A doctor may remove a small portion of a nerve or a sample of the skin to test for irregularities in nerve function or nerve endings.

The American Academy of Family Physicians recommends that peripheral neuropathy treatment address the underlying disease process, correct nutritional deficiencies, and aim to provide relief from symptoms.

Available treatments include medication, medical therapies and procedures, and alternative treatments.

Medications

Several different medications are available to treat neuropathy and its symptoms. These include:

• Medications for associated conditions: Conditions that may be causing polyneuropathy should be managed through various treatments, including medication if recommended by a doctor. Examples include insulin for diabetes and thyroid hormones for hypothyroidism.
• Pain medications: Over-the-counter pain relief can be beneficial for those with mild to moderate pain. These medications should not be taken on a long-term basis.
• Prescription medications: A doctor can prescribe some antidepressants, such as a group of drugs called tricyclic antidepressants (TCAs), including amitriptyline or nortriptyline. Another group of medications called serotonin-norepinephrine reuptake inhibitor (SNRIs), such as duloxetine may also help. Corticosteroid injections could possibly help treat mononeuropathies, and some seizure medications, such as gabapentin or pregabalin, may help.

Medical therapies

A variety of medical procedures are available. They include:

• Transcutaneous electrical nerve stimulation: Electrodes send a gentle current of electricity through the skin. This can help with pain and sensitivity.
• Plasma exchange: This type of therapy may benefit people with inflammatory or autoimmune conditions. The practitioner removes blood from the body and then separates antibodies and other proteins from the blood before returning the blood to the body.
• Immune globulin therapy: People with inflammatory and autoimmune conditions receive high levels of proteins to act as antibodies, which helps with immune function.
• Physical therapy: People with muscle weakness or coordination issues may find physical therapy helpful.
• Orthotic and other devices: Braces, canes, casts, splints, walkers, and wheelchairs may provide support and pain relief to those with neuropathy of the hands, feet, legs, and arms.

If nerve pressure is causing neuropathy, surgery may be an option.

Alternative treatments

Alternative and complementary treatments may offer relief to some people with polyneuropathy. Examples include:

• acupuncture
• chiropractic care
• massage
• meditation

However, researchers have not widely studied these remedies for polyneuropathy.

Preventing polyneuropathy involves limiting the risk factors and managing underlying conditions. A person with polyneuropathy may not be able to avoid all risk factors, but some lifestyle choices may help reduce the risk. These are:

• avoiding alcohol
• avoiding exposure to toxins, including cigarette smoke
• limiting factors that contribute to physical trauma or injury, such as repetitive actions and restrictive positions
• getting enough sleep and physical activity to support immune function
• eating a balanced diet rich in vitamins and minerals
• considering vitamin B12 supplements if following a vegan or vegetarian diet

Managing underlying conditions

Managing any underlying conditions can help prevent the onset of polyneuropathy. People with diabetes and other conditions related to polyneuropathy should closely follow their doctor’s treatment plan and ensure they attend all check-ups.

Outlook

The outlook for polyneuropathy varies and can depend on the underlying cause, which nerves are damaged, and the extent of the damage.

For some people, treating the underlying cause can lead to improvements. For others, the damage is permanent. In some cases, symptoms may worsen over time.

If a person experiences any symptoms of polyneuropathy, such as weakness, pain, or tingling in the hands or feet, it is important to contact a doctor.

Implementing a treatment plan as soon as possible is essential to help manage symptoms and prevent further nerve damage.

Polyneuropathy affects the nerves responsible for sensory neuropathy, motor neuropathy, and sensorimotor neuropathy. It can also affect the nerves responsible for functions such as digestion and heart rate.

There are over 100 different kinds of peripheral neuropathy, most of which are polyneuropathies.

Risk factors and causes of polyneuropathy can include diabetes, alcohol misuse, and certain autoimmune conditions.

Typical symptoms involve tingling, numbness, an inability to sense temperature changes, and more.

To diagnose polyneuropathy, a doctor will review a person’s symptoms, lifestyle factors, and medical history. The doctor may also perform a blood test or simple tests to check reflexes and other functions. Treatment can involve medication, therapy, or surgery.

A person should speak with a doctor if they are experiencing polyneuropathy symptoms.