Neuropathic Pain - A Guide Part 1

Today's post is part 1 of a two-part, general information post about neuropathic pain. Many people who have lived with neuropathy for some time, will already be aware of most of the things mentioned here but for those who are looking for general information, the posts from today and tomorrow are an excellent 'guide' to the disease. They come from howstuffworks.com (see link below) and the section is Discovery: fit and health. Useful for people new to neuropathy and to their friends and relatives who also want to know more.

Treatments for Neuropathic Pain
by Gerlinda Grimes

You're at the train station, sitting on a hard, cold bench with your foot tucked under you. Absorbed in your newspaper, at first you barely notice the numbness. Then, as you leap up to catch the train, you realize your foot has fallen asleep. You limp forward on your numb appendage, bracing yourself for the inevitable tingling, burning, stabbing pain, which will signal that your blood-deprived nerve endings are screaming back to life.

Neuropathic pain feels a lot like this. Neuropathy, from the Greek words neuro (nerve) and patheia (or pathos, meaning a disorder of), is an umbrella term that covers several conditions affecting the nerves.

Neuropathic pain can be difficult to diagnose and tricky to treat. It's most often a symptom of an underlying problem like diabetes, alcoholism or autoimmune disease. Neuropathy can also be caused by vitamin-B deficiency, tumors, infections, cancer treatments and certain hereditary disorders. Thirty percent of neuropathies are caused by diabetes; 40 percent are caused by other underlying conditions [source: Crosta]. In these cases, addressing the underlying cause will generally improve or relieve the neuropathy.

In almost 30 percent of neuropathic pain cases, however, the underlying cause of the pain is unknown [source: Crosta]. In these instances, and in situations where treatment of the underlying cause doesn't relieve the pain, other treatments are necessary. We'll explore five of them in this article.

Find out how antidepressants and anti-seizure medications help improve neuropathic pain next.

Tricyclics, SNRIs and Anticonvulsants: First-line Medications for Neuropathic Pain

Sometimes, treating the underlying cause doesn't relieve neuropathic pain, or no underlying cause can be found. In these cases, doctors prescribe medications to relieve neuropathy symptoms. Antidepressants (tricyclics and SNRIs) and anticonvulsants are considered first-line treatments for neuropathy pain.

SNRIs (serotonin-norepinephrine reuptake inhibitors) like Cymbalta (duloxetine) and Effexor (venlafaxine) and tricyclics like Elavil (amitriptyline) work by blocking proteins that act as re-uptakers, thereby increasing serotonin and norepinephrine levels. No one knows why, but patients with chronic pain often have low levels of these neurotransmitters. Therefore, taking drugs that increase these agents can be effective in decreasing pain. SNRIs are a newer class of drugs and have fewer side effects than the older tricyclics.

Anticonvulsants like Gabapentin prevent calcium from entering neurons and triggering a biochemical reaction that can result in neuropathic pain [source: Jeffries]. Studies show that about 43 percent of neuropathy patients who took Gabapentin at doses of 1200 milligrams or more showed moderate improvements, and one in three patients showed a substantial benefit [source: Moore, Wiffin, Derry and McQuay]. Gabapentin's main side effects are drowsiness, dizziness and diarrhea.

Neither tricyclics nor SNRIs work in every case. For cases where medications don't work or aren't effective enough, topical treatments may also be indicated. We discuss those next.

Topical Treatments for Neuropathic Pain

Even though anticonvulsants and antidepressants can treat neuropathic pain, about half of those who take them will not see any improvement [source: Moore, Wiffin, Derry and McQuay]. In these cases, topical pain relievers might help.

Lidocaine is one that has been around since the 1940s. It's so well-known as an analgesic that Meredith Grey, the protagonist of the popular television show "Grey's Anatomy," is quoted as saying, "I'm having a miscarriage. I need Lidocaine." in the nail-biting season six finale [source: Grey's Anatomy]. Lidocaine works on neuropathic pain by blocking voltage-gated sodium channels. Typically, it's prescribed in 5 percent patches. Up to three patches can be applied topically on a localized painful area and worn for 24 hours.

Capsaicin poses an alternative topical treatment. The active ingredient in capsaicin is derived from chili peppers, and capsaicin patches and creams are widely available over the counter for the deep-heating treatment of minor muscle pain. The dosages required for the treatment of chronic neuropathic pain, however, are much higher and require a prescription. In one study, patients applied a single high-dose (8 percent) capsaicin patch. Thirty-three percent of patients reported a 50 percent reduction in pain. Fifty percent reported at least a 30 percent reduction. The positive effects of the patch lasted around 12 weeks [source: Gever].

For cases where topical treatments don't provide enough relief or where neuropathic pain is random or not localized, patients may want to try something a little crazier than a cream.

PART TWO tomorrow

http://health.howstuffworks.com/medicine/modern-treatments/5-treatments-for-neuropathic-pain.htm