Neuropathic pain is a complex, chronic pain state that usually is accompanied by tissue injury. With neuropathic pain, the nerve fibers themselves may be damaged, dysfunctional, or injured. These damaged nerve fibers send incorrect signals to other pain centers. The impact of nerve fiber injury includes a change in nerve function both at the site of injury and areas around the injury.
One example of neuropathic pain is called phantom limb syndrome. This occurs when an arm or a leg has been removed because of illness or injury, but the brain still gets pain messages from the nerves that originally carried impulses from the missing limb. These nerves now misfire and cause pain.
Neuropathic pain often seems to have no obvious cause; but, some common causes of neuropathic pain include: alcoholism; amputation; back, leg, and hip problems; chemotherapy; diabetes; facial nerve problem; HIV infection or AIDS; Multiple sclerosis; Shingles; Spine surgery.
Neuropathic pain symptoms may include: shooting and burning pain; tingling and numbness.
The major categories of neuropathic pain include: * Toxic—the most common toxic condition causing neuropathic pain is a result of chemo-radiation in the treatment of cancer. Isoniazid and thallium are also known to cause neuropathic pain conditions. Exposure to chemicals like lead and arsenic also result in nerve damage. * Metabolic—Diabetes is clearly the major cause of neuropathic pain caused by metabolic dysfunction. Nutritional deficiencies like Beriberi (vitamin B1) also produce neuropathic pain. * Trauma—Trauma can result in phantom limb syndromes and/or complex regional pain syndromes (CRPS). * Compressive—both nerve entrapment and excessive external pressure on nerve axons can cause ischemic or distortional (stretching) changes. * Autoimmune—include chronic inflammatory demyelinating polyneuropathy (CIDP) and vasculitic neuropathy. * Infectious—viral conditions are known to result in long-standing neuropathic pain. * Congenital/Hereditary—Fabry’s Disease and Charcot-Marie-Tooth Disease (burning pain in extremities), amyloidosis also produce painful conditions.