Neuropathic pain is a chronic condition caused by damage within the nerve fibers, resulting in the delivery of incorrect signals to the brain. Neuropathic pain, a response to injury to the central nervous or peripheral nervous system, usually causes tissue damage. What makes neuropathic pain so difficult to treat is that it is not only chronic and severe, but unresponsive to simple analgesic relief.
In addition to stabbing, shocking or shooting (not aching) pain, patients may also experience numbness, tingling and weakness in the affected region of the body. They may also, because of exquisite nerve sensitivity, experience allodynia (pain provoked by gentle stimulus) or hyperalgesia (excessive pain provoked by a slight pain stimulus). A further addition to patient misery with neuropathic pain can be the insomnia suffered because of unremitting pain.
Causes of Neuropathic Pain
Neuropathic pain may occur as a result of several different factors, including surgery, certain diseases and underlying conditions. These may include disorders that cause nerve compression, such as:
- Nerve compression Injuries
- Spinal surgery
- Malignant or benign tumors
Neuropathic pain may also be caused by diseases, such as those listed below:
- Alcoholism
- Lyme disease
- Shingles
- Diabetes
- Amyotrophic lateral sclerosis (ALS)
- Autoimmune diseases like multiple sclerosis or lupus
Other miscellaneous causes of neuropathic pain may include chemotherapy or the ingestion of toxins, problems with facial nerves, like the trigeminal nerve, or phantom limb syndrome in which pain is experienced in a non-existent limb after amputation. In certain cases, nutritional deficiencies, especially a lack of sufficient vitamin B6 or B12 may result in neuropathic pain.
Treatments of Neuropathic Pain
There are a variety of treatments for neuropathic pain, depending on its cause. Where neuropathic pain results from a compressed nerve, as when a patient suffers from carpal tunnel syndrome, if more conservative methods are not effective, surgery may make a marked difference.
Where an underlying disease or condition is responsible for the neuropathic pain, more efficient treatment of the underlying condition, for example diabetes or alcoholism, may alleviate the problem. Other treatments of neuropathic pain are divided into two basic methods.
Pharmaceutical Treatments
While simple analgesics, such as aspirin and Tylenol, are not effective in combating neuropathic pain, other medications can help a great deal. These include various types of antidepressants, anticonvulsants, and opioid analgesics, such as tramadol and methadone. Sometimes anti-inflammatory medications may be helpful as well. Topical agents, like lidocaine may be used as auxiliary treatment for neuropathic pain. The efficacy of using cannabinoids in such treatment is presently being explored.
Minimally Invasive Treatments
When medications are not effective in treating neuropathic pain, minimally invasive treatments may be tried alone or in combination with medications. These treatments include pain management methods such as physical therapy, relaxation therapy, massage therapy, acupuncture or electrical stimulation. An implantable device called an intrathecal pump is presently in use as well. This pump, which delivers medication, usually morphine, directly to the spinal fluid through a small catheter, may be effective when other treatments are not.
Because neuropathic pain does not respond well to standard treatments, and because it may progressively worsen, a combination of therapies often provides the best treatment results. Since chronic pain is extremely stressful, and since stress tends to exacerbate pain, psychological counseling is often recommended as part of the treatment plan.
What is the first line of treatment for neuropathic pain?
First-line drugs for neuropathic pain include antidepressants (tricyclic antidepressants and serotonin–noradrenaline reuptake inhibitors) and anticonvulsants acting at calcium channels (pregabalin and gabapentin). Second- and third-line drugs for neuropathic pain include topical lidocaine and opioids.
