(See also Overview of Pain Overview of Pain Pain is an unpleasant sensation signaling actual or possible injury. Pain is the most common reason people seek medical care. Pain may be sharp or dull, intermittent or constant, or throbbing... read more .)
Neuropathic pain may result from
Compression of a nerve—for example, by a tumor, a ruptured disk Herniated Disk A herniated disk occurs when the tough covering of a disk in the spine tears or ruptures. The soft, jelly-like interior of the disk may then bulge out (herniate) through the covering. Aging... read more in the spine (causing low back pain and/or pain radiating down the leg), or pressure on a nerve in the wrist (causing carpal tunnel syndrome Carpal Tunnel Syndrome Carpal tunnel syndrome is a painful compression (pinching) of the median nerve as it passes through the carpal tunnel in the wrist. The cause of most cases of carpal tunnel syndrome is unknown... read more )
Nerve damage—as occurs in disorders that affect nerves (such as diabetes mellitus Diabetes Mellitus (DM) Diabetes mellitus is a disorder in which the body does not produce enough or respond normally to insulin, causing blood sugar (glucose) levels to be abnormally high. Urination and thirst are... read more or shingles Shingles Shingles is a painful skin rash caused by a viral infection that results from reactivation of the varicella-zoster virus, the virus that causes chickenpox. What causes the virus to reactive... read more )
Abnormal or disrupted processing of pain signals by the brain and spinal cord
Processing of pain is abnormal in phantom limb pain Neuropathic Pain Neuropathic pain is caused by damage to or dysfunction of the nerves, spinal cord, or brain. (See also Overview of Pain.) Neuropathic pain may result from Compression of a nerve—for example... read more , postherpetic neuralgia Postherpetic Neuralgia Postherpetic neuralgia is chronic pain in areas of skin supplied by nerves infected with herpes zoster ( shingles). Shingles is a painful rash of fluid-filled blisters that is caused by reactivation... read more (pain after shingles), and complex regional pain syndrome Complex Regional Pain Syndrome Complex regional pain syndrome is chronic neuropathic pain characterized by persistent burning or aching pain plus certain abnormalities that occur in the same area as the pain. Abnormalities... read more .
Neuropathic pain may also develop after surgery, such as removal of a breast (mastectomy) or lung surgery (thoracotomy).
Neuropathic pain can contribute to anxiety and/or depression. Anxiety and depression can also worsen pain.
Symptoms of Neuropathic Pain
Neuropathic pain may be felt as burning or tingling or as hypersensitivity to touch or cold. Hypersensitivity to touch is called allodynia. Even a light touch may cause pain.
Sometimes neuropathic pain is deep and aching.
If movement is painful, people may be reluctant to move the painful part of their body. In such cases, muscles that control the painful part may waste away, and movement may become more limited.
People continue to feel pain long after the cause resolves because structures in the nervous system have been changed, making the structures more sensitive to pain.
Diagnosis of Neuropathic Pain
A doctor's evaluation
Doctors base the diagnosis of neuropathic pain mainly on the following:
The likelihood of a nerve injury
Results of the examination
Depending on the symptoms, doctors may do tests to check for disorders that could be causing the pain. Tests may include magnetic resonance imaging (MRI), nerve conduction studies and electromyography Electromyography and Nerve Conduction Studies Diagnostic procedures may be needed to confirm a diagnosis suggested by the medical history and neurologic examination. Electroencephalography (EEG) is a simple, painless procedure in which... read more (EMG), and blood tests. Nerve conduction studies and EMG help doctors determine whether pain results from a problem with muscle or nerves and help them determine where the injury or dysfunction is located.
Treatment of Neuropathic Pain
Drugs (such as pain relievers, antidepressants, and antiseizure drugs)
Physical and/or occupational therapy
Surgery if needed
Stimulation of the spinal cord or nerves
A nerve block
Understanding what the nature of neuropathic pain is and what to expect often helps people feel more in control and better able to manage their pain.
Treatment of neuropathic pain can vary depending on the specific disorder causing it. For example, if the cause is diabetes, better control of blood sugar levels may help slow the progression of the nerve damage that causes pain.
Often, treatment of neuropathic pain begins with drugs. Drugs can help reduce the pain, making it less debilitating and disruptive, but it is often difficult to completely relieve the pain with drugs.
Other treatments include physical therapy, electrical stimulation of nerves or the spinal cord, nerve blocks Nerve block Chronic pain is pain that lasts or recurs for months or years. Usually, pain is considered chronic if it does one of the following: Lasts for more than 3 months Lasts for more than 1 month after... read more , and sometimes surgery.
Psychologic factors that may contribute to the pain, such as anxiety Treatment Anxiety is a feeling of nervousness, worry, or unease that is a normal human experience. It is also present in a wide range of psychiatric disorders, including generalized anxiety disorder,... read more and depression Treatment A short discussion of prolonged grief disorder. Depression is a feeling of sadness and/or a decreased interest or pleasure in activities that becomes a disorder when it is intense enough to... read more , if present, are also treated from the beginning.
Pain relievers (analgesics) may be given to reduce neuropathic pain.
Pain relievers used to treat neuropathic pain include the following:
Adjuvant analgesics Adjuvant Analgesics Pain relievers (analgesics) are the main drugs used to treat pain. Doctors choose a pain reliever based on the type and duration of pain and on the drug's likely benefits and risks. Most pain... read more are drugs that change the way nerves process pain. These drugs can reduce pain intensity. Many adjuvant analgesics are usually used to treat other problems (such as seizures or depression), but they were found to sometimes relieve pain, including neuropathic pain. These drugs include antidepressants Drug therapy for depression A short discussion of prolonged grief disorder. Depression is a feeling of sadness and/or a decreased interest or pleasure in activities that becomes a disorder when it is intense enough to... read more (such as amitriptyline, desipramine, and venlafaxine) and antiseizure drugs Antiseizure drugs In seizure disorders, the brain's electrical activity is periodically disturbed, resulting in some degree of temporary brain dysfunction. Many people have unusual sensations just before a seizure... read more (such as gabapentin), which are commonly used to treat neuropathic pain.
Opioid analgesics Opioid Pain Relievers Pain relievers (analgesics) are the main drugs used to treat pain. Doctors choose a pain reliever based on the type and duration of pain and on the drug's likely benefits and risks. Most pain... read more partially relieve neuropathic pain in some people, but the risk of side effects is usually higher than that with adjuvant analgesics.
However, drugs often provide only partial relief and typically only in fewer than half of people with neuropathic pain.
Physical and occupational therapy
Physical therapy Physical Therapy (PT) Physical therapy, a component of rehabilitation, involves exercising and manipulating the body with an emphasis on the back, upper arms, and legs. It can improve joint and muscle function, helping... read more and occupational therapy Occupational Therapy (OT) Occupational therapy, a component of rehabilitation, is intended to enhance a person's ability to do basic self-care activities, useful work, and leisure activities. These activities include... read more help people do the following:
Continue to move the painful part and thus prevent muscles from wasting away
Increase or maintain the joint’s range of motion
Decrease sensitivity of the affected area to pain
Surgery may be needed if the pain results from an injury that puts pressure on a nerve.
Electrical stimulation Electrical stimulation Professional rehabilitation therapists treat pain and inflammation. Such treatment makes movement easier and enables people to participate more fully in rehabilitation. Techniques used include... read more (from electrodes placed over the spine or other areas) may be helpful for certain types of chronic neuropathic pain. In transcutaneous electrical nerve stimulation Nondrug Pain Treatments Pain relievers (analgesics) are the main drugs used to treat pain. Doctors choose a pain reliever based on the type and duration of pain and on the drug's likely benefits and risks. Most pain... read more (TENS), a gentle electric current is applied through electrodes placed on the skin’s surface. TENS units are available over the counter. For this treatment, stimulation pads are placed around the painful area.
Peripheral nerve stimulation involves placing thin wires under the skin to stimulate an individual peripheral nerve. (Peripheral nerves are those outside the brain and spinal cord.) The wires are attached to a small device (stimulator) placed on the skin's surface. This treatment is particularly effective for neuropathic pain, and it targets the painful area better than TENS. Placing the wires under the skin is a minimally invasive outpatient procedure because it requires making small cuts into the skin.
Spinal cord stimulation may be used to relieve neuropathic pain in people with nerve damage after back surgery or with complex regional pain syndrome Complex Regional Pain Syndrome Complex regional pain syndrome is chronic neuropathic pain characterized by persistent burning or aching pain plus certain abnormalities that occur in the same area as the pain. Abnormalities... read more . This treatment involves implanting a spinal cord stimulator under the skin, usually in a buttock or abdomen. Like a heart pacemaker, this device generates electrical impulses. Small wires (leads) from the device are placed in the space around the spinal cord (epidural space). These leads transmit impulses to the spinal cord. The impulses change the way pain signals are sent to the brain and thus change how unpleasant symptoms are perceived.
Nerve blocks are used to disrupt a nerve pathway that transmits or enhances pain signals. Nerve blocks may be used in people with severe, persistent pain when drugs cannot relieve the pain. Various techniques may be used:
Injecting the area around the nerves with a local anesthetic to prevent the nerves from sending pain signals (doctors commonly use ultrasonography to help them locate the nerves to be treated)
Injecting the area around collections of nerve cells called ganglia to help regulate the transmission of pain signals
Injecting a caustic substance (such as phenol) into a nerve to destroy it
Freezing a nerve (cryotherapy)
Burning a nerve with a radiofrequency probe