Polyneuropathy is a condition in which a person’s peripheral nerves are damaged. These are nerves that run throughout your body. Polyneuropathy affects the nerves in your skin, muscles, and organs. When nerves are damaged, they can’t send regular signals back to your brain. This condition does not affect the nerves in your brain or spine, however.

There are two major categories of polyneuropathy: acute and chronic.

Acute polyneuropathy

Acute forms happen when you get the condition suddenly and the symptoms are severe. This type is common when you have an autoimmune reaction or infection causing the nerve damage. A disorder like Guillain-Barré syndrome may be the cause. Acute cases can often be treated successfully in a short time.

Chronic polyneuropathy

Chronic forms happen when your symptoms last a long time and can’t be treated quickly. This type can be caused by underlying conditions, such as diabetes or kidney failure. There can be many different causes of chronic polyneuropathy. It’s not always easy to figure out the cause, and some cases have no clear cause.

Symptoms can vary depending on what’s causing them. The most common symptoms include:

  • random, odd sensations, known as paresthesia
  • sudden sharp pains
  • burning or tingling sensations, especially in your feet and hands, known as distal polyneuropathy
  • feeling extremely sensitive to touch, known as allodynia
  • numbness
  • feeling weak in your legs or arms (sometimes due to weak or atrophied muscles)
  • inability to walk straight, leading to stumbling or falling
  • trouble swallowing

Causes may be idiopathic, acquired, and hereditary.

Idiopathic polyneuropathy means that the cause of the nerve damage isn’t known.

Acquired means the polyneuropathy is caused by an event that happens outside the body, such as a traumatic injury or an infection. It may also be caused by an underlying condition that’s not treated well or causing complications, such as a vitamin deficiency, diabetes, or cancer.

Hereditary polyneuropathy is passed on to you genetically by one of your parents. These conditions usually cause slow and gradual nerve damage, such as in Charcot-Marie-Tooth disease.

Acute forms can happen because of several different causes. These include:

  • certain insecticides
  • autoimmune disorders in which your body attacks the myelin in your nerve cells, such as Guillain-Barré syndrome (GBS)
  • some antibiotics, anticonvulsants, and sedatives
  • cancer, especially those that directly affect the nervous system, such as multiple myeloma

Chronic forms are often idiopathic, but they can also have causes such as:

  • alcoholism or drinking a lot of alcohol in general
  • diabetes and a lack of control over blood sugar levels
  • certain heavy metals
  • nutritional or vitamin deficiencies, especially thiamin or vitamin B-12
  • hypothyroidism
  • kidney failure
  • some cancers, including lung cancer

Treatment of polyneuropathy depends on the condition that caused it. It can also depend on where in your body you feel symptoms. In some cases, your doctor may give you pain medications to help manage the pain and discomfort from nerve damage. These can include nonsteroidal anti-inflammatory drugs (NSAIDs).

Lifestyle changes

Making lifestyle changes may help treat your polyneuropathy. Drinking less alcohol or avoiding certain repetitive tasks can help relieve your symptoms.

If a toxin or chemical in your environment is causing your polyneuropathy, your doctor may urge you to find a way to limit your exposure to it.

For traumatic injuries

If you’re having polyneuropathy after a traumatic injury, your doctor may recommend physical therapy. This can help you regain full control of your body. You can also learn how to manage the nerve pain and sensations that may have been caused by the injury.

For autoimmune conditions

If an autoimmune condition is causing your polyneuropathy, your doctor may suggest different treatments or therapies. These can include:

  • corticosteroids
  • immune globulin injected intravenously (directly into your veins)
  • plasma exchange, which removes toxins from your blood

For diabetes

If diabetes is causing your polyneuropathy, your doctor will likely recommend a treatment plan to help you get your blood sugar levels under control. This type of treatment plan often includes oral medications or self-administered insulin injections. In rare cases of Type 1 diabetes, your doctor may suggest a surgery to transplant insulin-producing cells (known as islet cells) from a donor pancreas to help your body produce and release more insulin. This is a significant surgery and will likely only be recommended if all other treatments fail.

For cancer

If cancer cells or cancerous tumors are causing your polyneuropathy, your doctor may recommend surgery to remove the cells or tumors. Chemotherapy may help remove tumors or cancerous cells that are putting stress or pressure on your nerves.

Your overall health may reveal your risk factors for polyneuropathy. Common risk factors include:

  • diabetes mellitus
  • kidney or liver conditions
  • autoimmune disorders
  • alcoholism
  • infections, including HIV, shingles, and Lyme disease
  • using certain parts of your body repetitively (such as for an industrial job), also called repetitive motion injury

Your doctor will likely perform several tests to decide whether you have polyneuropathy as well as what’s causing it.

A full physical exam will help your doctor discover what parts of your body are most affected by your nerve damage and pain. A physical can also help your doctor find any weak or atrophied muscles that may have been affected by nerve damage.

Your doctor may also perform electrical nerve and muscle tests to see the extent of nerve damage.

A blood test, urine samples, and biopsy of the area affected by nerve damage (sometimes including your nerves, too) will also help your doctor figure out the cause and extent of polyneuropathy. Other tests may be necessary if your doctor suspects an underlying condition. A spinal tap or lumbar puncture can help your doctor find out if your protein and white blood cell levels are abnormal. Abnormal results can mean that you have Guillain-Barré syndrome.

You can help reduce nerve damage by catching certain conditions early. That way, you can get treatment before pain or discomfort becomes difficult to manage.

If you have any noticeable symptoms of polyneuropathy, especially after a major injury, see your doctor as soon as possible. They can determine if you have any conditions that may be causing polyneuropathy. Treating your symptoms early is the best way to keep polyneuropathy from disrupting your life.