(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 visit their doctor. 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 the whole body (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 only one or a few parts (such as 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 Phantom limb 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 characterized by persistent burning or aching pain plus certain abnormalities that occur in the same area as the pain. Abnormalities include increased or decreased... read more .
Neuropathic pain can contribute to anxiety and/or depression. Anxiety and depression can also worsen pain.
Neuropathic pain may also develop after surgery, such as removal of a breast (mastectomy) or lung surgery (thoracotomy).
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.
Doctors base the diagnosis of neuropathic pain mainly on the following:
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 result from a problem with muscle or nerves.
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. 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 In some cases, treating the underlying disorder eliminates or minimizes the pain. For example, setting a broken bone in a cast or giving antibiotics for an infected joint helps reduce pain.... read more are drugs that change the way the nerves process pain and that thus affect pain intensity. Many of these drugs 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 and antiseizure drugs, which are commonly used to treat neuropathic pain.
Opioid analgesics Opioid Analgesics In some cases, treating the underlying disorder eliminates or minimizes the pain. For example, setting a broken bone in a cast or giving antibiotics for an infected joint helps reduce pain.... read more partially relieve neuropathic pain in some people, but the risk of side effects is usually higher than that with adjuvant analgesics.
Drugs applied to the skin In some cases, treating the underlying disorder eliminates or minimizes the pain. For example, setting a broken bone in a cast or giving antibiotics for an infected joint helps reduce pain.... read more (topical drugs), such as a capsaicin cream or a patch that contains lidocaine (a local anesthetic), may be effective.
However, drugs often provide only partial relief and typically only in fewer than half of people with neuropathic pain.
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:
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) is helpful for certain types of chronic neuropathic pain. In transcutaneous electrical nerve stimulation In some cases, treating the underlying disorder eliminates or minimizes the pain. For example, setting a broken bone in a cast or giving antibiotics for an infected joint helps reduce pain.... read more (TENS), a gentle electric current is applied through electrodes placed on the skin’s surface. Often, people are taught to use the TENS device, so that they can use it as needed.
Peripheral nerve stimulation involves placing electrodes under the skin to stimulate an individual peripheral nerve. (Peripheral nerves are those outside the brain and spinal cord.) The electrodes are often more effective than TENS for neuropathic pain, but placing them under the skin is an invasive procedure because it requires making small cuts into the skin.
Spinal cord stimulation is commonly 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 characterized by persistent burning or aching pain plus certain abnormalities that occur in the same area as the pain. Abnormalities include increased or decreased... 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 (called cryotherapy)
Burning a nerve with a radiofrequency probe
Phantom limb pain cannot be caused by a problem in the limb. Rather, it must be caused by a change in the nervous system above the site where the limb was amputated. But the brain misinterprets the nerve signals as coming from the amputated limb. Usually, the pain seems to be in the toes, ankle, and foot of an amputated leg or in the fingers and hand of an amputated arm. The pain may resemble squeezing, burning, or crushing sensations, but it often differs from any sensation previously experienced. For some people, phantom limb pain occurs less frequently as time passes, but for others, it persists.
Massaging the remaining (residual) part of the limb sometimes relieves phantom limb pain. If massaging is ineffective, pain relievers (analgesics) can be taken.
Typically, nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, or adjuvant analgesics Adjuvant Analgesics In some cases, treating the underlying disorder eliminates or minimizes the pain. For example, setting a broken bone in a cast or giving antibiotics for an infected joint helps reduce pain.... read more , such as nortriptyline or duloxetine (antidepressants) or gabapentin or pregabalin (antiseizure drugs), are used. But sometimes opioid pain relievers are required. If opioid pain relievers do not relieve the pain or if a person needs to take opioids for a long time, a pain management specialist may be asked to supervise treatment.
Treatment may include using mechanical devices (such as a vibrator), ultrasound, and spinal cord stimulation In some cases, treating the underlying disorder eliminates or minimizes the pain. For example, setting a broken bone in a cast or giving antibiotics for an infected joint helps reduce pain.... read more . Spinal cord stimulation involves surgically placing a spinal cord stimulator (a device that generates electrical impulses) under the skin, usually in a buttock or abdomen. Small wires (leads) from the device are placed in the space around the spinal cord (epidural space). These impulses change the way pain signals are sent to the brain and thus change how unpleasant symptoms are perceived.
Other nondrug treatments that may help include transcutaneous electrical nerve stimulation In some cases, treating the underlying disorder eliminates or minimizes the pain. For example, setting a broken bone in a cast or giving antibiotics for an infected joint helps reduce pain.... read more (TENS) and acupuncture Acupuncture Acupuncture, a therapy within traditional Chinese medicine, is one of the most widely accepted CAM therapies in the Western world. Licensed practitioners do not necessarily have a medical degree... read more .
Mirror therapy may be helpful. A health care practitioner teaches people how to use this therapy. People sit with a large mirror facing their unaffected limb and hiding their missing limb. The mirror reflects the image of the unaffected limb, giving people the impression that they have two normal limbs. People are then instructed to move the unaffected limb while watching its reflected image. Thus, people feel as if they are moving two normal limbs. If people do this exercise for 30 minutes a day for 4 weeks, pain may be substantially reduced. This therapy changes the pathways in the brain that interpret pain signals in the body.
Shingles is caused by reactivation of the varicella-zoster virus, the virus that causes chickenpox Chickenpox Chickenpox is a highly contagious viral infection with the varicella-zoster virus that causes a characteristic itchy rash, consisting of small, raised, blistered, or crusted spots. Chickenpox... read more . Some people who have had shingles continue to have pain (postherpetic neuralgia) long after the rash has gone away.
What causes postherpetic neuralgia is unknown. But it is more likely to develop if the shingles rash is severe, if people are older when shingles develops, and if shingles affects certain areas of the body. For example, if shingles affects the face, postherpetic neuralgia is more likely to develop than if shingles affects the torso.
The pain may be felt as any combination of the following:
The area where the rash first occurred becomes painful and tender to the touch.
The pain may be debilitating. The pain may subside within several months or last for years.
Vaccination with the shingles (herpes zoster) vaccine Herpes Zoster Vaccine There are two herpes zoster vaccines. The newer herpes zoster vaccine is preferred over the older herpes zoster vaccine because it provides better and longer-lasting protection. The newer vaccine... read more can help reduce the risk of getting shingles. A new shingles vaccine has replaced an older one and provides protection longer, even in people whose immune system is weakened. It can also help reduce the risk of developing postherpetic neuralgia in people who get shingles despite being vaccinated.
No treatment is routinely effective. Treatment of postherpetic neuralgia may include
Pain relievers (analgesics)
Adjuvant analgesics, including certain antiseizure drugs (such as gabapentin and pregabalin) and antidepressants (such as amitriptyline)
Lidocaine ointment or patch applied to the affected area
Capsaicin cream applied to the affected area after the area is numbed with lidocaine
Botulinum toxin A injected into the affected area
Sometimes opioid analgesics are needed.