Defining Neuropathic Pain
Neuropathic pain is caused by damage or injury to the nerves that transfer information between the brain and spinal cord from the skin, muscles and other parts of the body. The pain is usually described as a burning sensation and affected areas are often sensitive to the touch. It is often described as a shooting pain and can go away on its own, but is often chronic.
Examples include post herpetic (or post-shingles) neuralgia, reflex sympathetic dystrophy / causalgia (nerve trauma), components of cancer pain, phantom limb pain, entrapment neuropathy (e.g., carpal tunnel syndrome), and peripheral neuropathy (widespread nerve damage). Among the many causes of peripheral neuropathy, diabetes is the most common, but the condition can also be caused by chronic alcohol use, exposure to other toxins (including many chemotherapies), vitamin deficiencies, and a large variety of other medical conditions--it is not unusual for the cause of the condition to go undiagnosed.
Neuropathic pain is the result of an injury or malfunction in the peripheral or central nervous system. The pain is often triggered by an injury, but this injury may or may not involve actual damage to the nervous system. Nerves can be infiltrated or compressed by tumors, strangulated by scar tissue, or inflamed by infection. The pain frequently has burning, lancinating, or electric shock qualities. Persistent allodynia, pain resulting from a nonpainful stimulus such as a light touch, is also a common characteristic of neuropathic pain. The pain may persist for months or years beyond the apparent healing of any damaged tissues. In this setting, pain signals no longer represent an alarm about ongoing or impending injury, instead the alarm system itself is malfunctioning.
our nervous system is damaged or not working correctly. You can feel pain from any of the various levels of the nervous system—the peripheral nerves, the spinal cord and the brain. Together, the spinal cord and the brain are known as the central nervous system. Peripheral nerves are the ones that are spread throughout the rest of your body to places likes organs, arms, legs, fingers and toes.
Damaged nerve fibers send the wrong signals to pain centers. Nerve function may change at the site of the nerve damage, as well as areas in the central nervous system (central sensitization).
Neuropathy is a disturbance of function or a change in one or several nerves. Diabetes is responsible for about 30% of neuropathy cases. It is not always easy to tell the source of the neuropathic pain. There are hundreds of diseases that are linked to this kind of pain.
Neuropathic pain is frequently chronic, and tends to have a less robust response to treatment with opioids, but may respond well to other drugs such as anti-seizure and antidepressant medications. Usually, neuropathic problems are not fully reversible, but partial improvement is often possible with proper treatment.
Neuropathic pain can be caused by diseases, including:
Alcoholism.
Diabetes.
Facial nerve problems.
HIV infection or AIDS.
Central nervous system disorders (stroke, Parkinson’s disease, multiple sclerosis, etc.)
Complex regional pain syndrome.
Shingles. (Pain that continues after your bout with shingles ends is called postherpetic neuralgia.)
Other causes include:
Chemotherapy drugs (cisplatin, paclitaxel, vincristine, etc.).
Radiation therapy.
Amputation, which can cause phantom pain.
Spinal nerve compression or inflammation.
Trauma or surgeries with resulting nerve damage.
Nerve compression or infiltration by tumors.
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