Neuropathy is a disorder of one or more peripheral nerves ­– the nerves outside of the brain and spine. There are many kinds of neuropathies and many causes.

Up to 30 million Americans experience some degree of neuropathy, making it more common than diseases like diabetes. As many as 70 percent of people with diabetes have some form of neuropathy.

To understand a neuropathy, it helps to know the type of nerve involved.

The nervous system is divided into two categories:

  • Peripheral nervous system includes all nerves connecting the brain and spinal cord to the body. Motor nerves send signals from the brain to muscle, sensory nerves send sensations to the brain for processing, and other nerves carry signals to and from internal organs to keep them working.
  • Central nervous system includes the brain, brainstem connecting the brain to the spinal cord, and the spinal cord.

When one peripheral nerve is affected, it is called mononeuropathy. Examples are Carpal Tunnel Syndrome, in which the median nerve in the wrist is compressed, causing numbness, tingling and weakness in the hand; and Cubital Tunnel Syndrome, when the same symptoms result from compression of the ulnar nerve where it passes through the elbow.

When two or more peripheral nerves are affected, it is called polyneuropathy. One example is diabetic neuropathy, which typically starts in the toes and moves up the legs to the hands and arms.

Autonomic neuropathy affects nerves that control bodily functions – digestion, heart rate, blood pressure, sweating – that occur without our conscious control.

Symptoms of Neuropathy

The type of nerve involved determines the symptoms.

Neuropathy in motor nerves can cause:

  • Weakness
  • Loss of muscle tissue or atrophy
  • Muscle cramps
  • Fatigue

Neuropathy in sensory nerves can cause:

  • Numbness or reduced sensation
  • Tingling, pin prick or stabbing sensations
  • Burning
  • Sensations of cold or freezing
  • Tightness or squeezing
  • Sensation that something is under your foot or toes
  • Sensation of walking on pebbles or blocks of wood
  • Heightened sensitivity to touch making it uncomfortable or painful
  • Throbbing or aching
  • Trouble balancing
  • Neuropathy in small fiber sensory nerves can cause a painful, burning sensation.

Neuropathy in autonomic nerves can cause:

  • Lightheadedness, dizziness and fainting
  • Heart arrhythmias
  • Constipation or diarrhea
  • Bloating or feeling too full after small amounts of food
  • Bladder trouble
  • Sweating too much or too little
  • Sexual dysfunction or reduced libido
  • Vision impairment
  • Dry mucous membranes

Causes of Peripheral Neuropathy

  • Diabetes. Diabetic neuropathies can affect any type of peripheral nerve and cause any neuropathy symptom. Thyroid and kidney disorders also can cause neuropathy.
  • Genetic abnormalities can cause inherited neuropathies such as Charcot Marie Tooth disease and Fabry’s disease.
  • Exposure to chemicals such as alcohol or chemotherapy can cause nerve injury and toxic neuropathies.
  • Deficiency syndromes, especially of vitamins B12, B6 and B1.
  • Autoimmune disorders like Sjögren's Syndrome, lupus, rheumatoid arthritis, fibromyalgia, Guillain-Barré Syndrome and chronic inflammatory demyelinating polyradiculoneuropathy cause inflammation that can damage nerves and lead to neuropathy.
  • Mechanical trauma such as Carpal Tunnel Syndrome. Nerves also can be damaged during surgery or by trauma, compression or overuse.
  • Cancerous tumors can compress a nerve or grow in the nerve. Cancer also can prompt the immune system to mistakenly identify the nerve as foreign and attack it.
  • Infection like HIV, hepatitis, West Nile virus and Lyme disease.
  • Vasculitis, which can disrupt the blood supply to nerves.

Up to 30 percent of the time, a neuropathy is considered “idiopathic” because no cause can be identified.

Screening & Diagnosing Neuropathy

Because peripheral neuropathy has many potential causes, your doctor may order a variety of tests, in addition to a physical and neurologic exam and full medical history.

You may need to get some of the following tests:

  • Blood tests. We look for vitamin deficiencies, diabetes, abnormal immune function and other signs of conditions that can cause peripheral neuropathy.
  • Imaging tests. Using CT or MRI scans, we can find compressed nerves, tumors or other abnormalities.
  • Nerve tests. The most common is electromyography (EMG), which tracks electrical activity in muscles to find any nerve damage. For this test, we will insert a thin needle/electrode into the muscle and have you contract the muscle. In the same appointment, we will place flat electrodes on the skin and send a low electric current through to stimulate the nerves. This nerve conduction study tells us the nerves' response.
  • Sweat test. We will examine your body’s ability to sweat.
  • Sensory tests. These record how your body feels touch, vibration and temperature.
  • Nerve biopsy. For this, we must remove a small piece of a nerve to look for abnormalities.
  • Skin biopsy. By removing a small piece of skin, we can see if there are fewer nerve endings than there should be.


Meet our Neuropathy Specialists:

Carl Boland



Medical Group The Ayer Neuroscience Institute
North Haven, CT 06473
More Locations
Hartford, CT 06106
Annie Daniel



Medical Group The Ayer Neuroscience Institute at Hartford Hospital Department of Neurology
Medical Office Building
Hartford, CT 06106
Ninad Desai



Medical Group Hartford HealthCare Medical Group at St. Vincent's Medical Center Department of Neurology
Bridgeport, CT 06606
Barry Gordon



Medical Group The Ayer Neuroscience Institute
Meriden, CT 06451
Brandon Ito



Medical Group The Ayer Neuroscience Institute
Meriden, CT 06451
Zara Khan



Medical Group The Ayer Neuroscience Institute
Spine Wellness Center
Westport, CT 06880
More Locations
Stamford, CT 06905
Lucas Meira Benchaya



Medical Group The Ayer Neuroscience Institute at Hartford Hospital Department of Neurology
Medical Office Building
Hartford, CT 06106
More Locations
Torrington, CT 06790
John Tauro



Medical Group The Ayer Neuroscience Institute
Norwich, CT 06360
David Tinklepaugh



Medical Group The Ayer Neuroscience Institute Neuromuscular Medicine
Mystic, CT 06355