YOUR HEALTH

DEAR DR. DONOHUE: My right foot burns like it's on fire. There's nothing on the skin, and I can move my foot fine. My doctor gave me a cream to put on my foot, but it's not doing anything. What do you think I have? -J.M.

ANSWER: I'd consider a neuropathy. Neuropathies are nerve disorders brought on by many different conditions -diabetes, heredity, Lyme disease, immune attacks, compression from adjacent structures, genes and vitamin deficiencies. The pain that follows a shingles outbreak is a neuropathy.

Since there are two kinds of nerves, there are two kinds of neuropathies. Motor nerves conduct impulses to muscles to get them to move. Sensory nerves deliver information from

the skin and the body's interior to the brain, alerting it to temperature change, touch, pain and a thousand other sensations. There is a third kind of nerve, one that combines both sensory function and motor function.

If motor nerves are the primary target of neuropathy, then muscle weakness is the consequence. People can have an unsteady walk, or they find it impossible to pick up a foot when taking a step. If a sensory nerve is involved, intractable pain is the consequence. If a nerve that is both motor and sensory is involved, then both weakness and pain arrive together.

You should ask your doctor for a referral to a neurologist, who can investigate nerve function with special equipment. If you have a painful

neuropathy, there are many medicines that can lessen the pain. Amitriptyline, Cymbalta, Neurontin, Lidoderm skin patches and Zostrix ointment are choices. Lyrica is a new product for diabetic neuropathy.

Other treatments are available for motor neuropathies.

The Neuropathy Association is standing by, ready to help all with neuropathies. Its toll-free number and Web site are 1-800-247-6968 and www.neuropathy.org.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL32853-6475.