Peripheral Neuropathy

Peripheral neuropathy has many potential causes. Besides a physical exam, which may include blood tests, diagnosis usually requires:

A full medical history. Your doctor will review your medical history, including your symptoms, lifestyle, exposure to toxins, drinking habits and a family history of nervous system (neurological) diseases.

Neurological examination. Your doctor might check your tendon reflexes, your muscle strength and tone, your ability to feel certain sensations, and your posture and coordination.

Tests

Your doctor may order tests, including:

Blood tests. These can detect vitamin deficiencies, diabetes, abnormal immune function and other indications of conditions that can cause peripheral neuropathy.

Imaging tests. CT or MRI scans can look for herniated disks, pinched (compressed) nerves, tumors or other abnormalities affecting the blood vessels and bones.

Nerve function tests. Electromyography (EMG) records electrical activity in your muscles to detect nerve damage. A thin needle (electrode) is inserted into the muscle to measure electrical activity as you contract the muscle.

At the same time your doctor or an EMG technician obtains an electromyogram, he or she typically performs a nerve conduction study. Flat electrodes are placed on the skin and a low electric current stimulates the nerves. Your doctor will record your nerves' responses to the electric current.

Other nerve function tests. These might include an autonomic reflex screen that records how the autonomic nerve fibers work, a sweat test that measures your body's ability to sweat, and sensory tests that record how you feel touch, vibration, cooling and heat.

Nerve biopsy. This involves removing a small portion of a nerve, usually a sensory nerve, to look for abnormalities.

Skin biopsy. Your doctor removes a small portion of skin to look for a reduction in nerve endings.

Treatment goals are to manage the condition causing your neuropathy and to relieve symptoms. If your lab tests indicate no underlying condition, your doctor might recommend watchful waiting to see if your neuropathy improves.

Medications

Besides medications used to treat conditions associated with peripheral neuropathy, medications used to relieve peripheral neuropathy signs and symptoms include:

Pain relievers. Over-the-counter pain medications, such as nonsteroidal anti-inflammatory drugs, can relieve mild symptoms. For more-severe symptoms, your doctor might prescribe painkillers.

Medications containing opioids, such as tramadol (Conzip, Ultram, others) or oxycodone (Oxycontin, Roxicodone, others), can lead to dependence and addiction, so these drugs generally are not prescribed unless all other treatments fail.

Anti-seizure medications. Medications such as gabapentin (Gralise, Neurontin, Horizant) and pregabalin (Lyrica), developed to treat epilepsy, may relieve nerve pain. Side effects can include drowsiness and dizziness.

Topical treatments. Capsaicin cream, which contains a substance found in hot peppers, can cause modest improvements in peripheral neuropathy symptoms. You might have skin burning and irritation where you apply the cream, but this usually lessens over time. Some people, however, can't tolerate it.

Lidocaine patches are another treatment you apply to your skin that might offer pain relief. Side effects can include drowsiness, dizziness and numbness at the site of the patch.

Antidepressants. Certain tricyclic antidepressants, such as amitriptyline, doxepin (Silenor, Zonalon) and nortriptyline (Pamelor), have been found to help relieve pain by interfering with chemical processes in your brain and spinal cord that cause you to feel pain.

The serotonin and norepinephrine reuptake inhibitor duloxetine (Cymbalta, Drizalma Sprinkle) and the extended-release antidepressants venlafaxine (Effexor XR) abd desvenlafaxine (Pristiq) also might ease the pain of peripheral neuropathy caused by diabetes.

Side effects of antidepressants may include dry mouth, nausea, drowsiness, dizziness, changes in appetite, weight gain and constipation.