Herpes zoster (shingles) affects up to a million people per year, and 200,000 Americans are affected by the painful aftermath (post-herpetic neuralgia) which is more likely to strike those over the age of 60. The treatment of post-herpetic neuralgia, which results from the herpes virus invading and destroying nerves and even spinal cord tissue, is often complex. Treatments include medications that reduce the transmission of pain impulses in the nerves as well as reducing the area of pain in skin and nerve receptors.
Numerous medications are available and include analgesics, antidepressants (not for depression but to treat the pain itself), antiseizure medicine (not for seizures but to treat nerve pain), capsaicin, and most recently the drug Neurontin, which at high dosages has shown itself to be very effective in treating the symptoms of post-herpetic neuralgia. Sometimes nerve blocks are required and can be dramatically helpful as well; electrical stimulation of the skin is another option.
A variety of skin patches are available, including those that contain lidocaine, such as Lidoderm. Lidoderm is the first product ever approved for the relief of pain specifically associated with post-herpetic neuralgia, and is thought to stabilize nerve membranes and thus produce an analgesic effect.
The patch is applied to intact skin covering the most painful areas and causes a reduction in pain under and surrounding the patch. It is not generally recommended to be applied to areas of broken or seriously inflamed skin.
The advantages of the patch are that it is easy to apply and the medicine is generally not absorbed into the system (although overdosing or using it for more than 12 hours out of 24 can be toxic). The patch may also reduce irritation from clothing or inadvertent stimulation. Modest to moderate relief can be expected. The drug is marketed by Endo Laboratories.