One of the most common complications of diabetes is diabetic neuropathy, diabetes-induced damage to the nerves that run throughout the body, connecting the spinal cord to muscles, skin, blood vessels, and other organs. Diabetic neuropathy can be painful and disabling. Fortunately, the severest forms of neuropathy do not occur often.
Some symptoms of peripheral neuropathy (so named because it occurs outside
the brain and spinal cord) occur when the nerve conduction is lost, such as
muscular weakness, loss of feeling, even loss of functions not normally under
conscious control, like digestion. These neuropathy symptoms include prickling,
tingling, burning, aching, or sharp jabs of needle-like pain. This pain can
be severe and incapacitating. Or, there can be complete numbness. Different
types of neuropathy symptoms can occur together. It is common to have pain even
though many fibers have been lost.
What Causes Neuropathy?
Researchers do not yet know what specifically causes diabetic neuropathy. Glucose control seems to play a prominent role -- as neuropathy is more likely to affect people who have had diabetes for a long time or whose glucose control is poor.
Neuropathy can be prevented, slowed, or diminished, in some cases. The Diabetes Control and Complications Trial studied complications in people on tight glucose control and those using regular diabetes treatment. Only one-third as many people in the tight-control group got neuropathy as in the standard-treatment group. In addition, avoiding alcohol and cigarettes will probably help protect your nerves from damage and prevent against neuropathy.
Treatment for Neuropathy
Researchers are still looking for a way to heal nerves damaged by neuropathy (see Anodyne Therapy article in this issue). Right now, most treatment aims to relieve the painful symptoms of neuropathy.
The U.S. Food and Drug Administration (FDA) recently approved the first treatment specifically for pain associated with diabetic neuropathy. This chemical, Eli Lilly's Cymbalta (duloxetine hydrochloride) is already in world-wide use as a treatment for depression. It targets two chemical messengers in the body, serotonin and norepinephrine, believed to play a role in pain perception. Other antidepressants, not approved by the FDA for this use, are also employed, "off label," to relieve nerve pain -- but Cymbalta is the first to be fully tested by the FDA for this use and found effective. For more information about Cymbalta (which is available now) talk to your doctor, telephone the Lilly Answers Center: 1-800-545-5979, or visit (www.lilly.com), or (www.cymbaltanews.com)