PHN (post-herpetic neuralgia) is hard to treat

DEAR DR. ROACH: I am 77 and developed shingles in December 2016. Although my blisters are long gone, I still have pain and topical discomfort, which I know are from the nerve endings. My doctor says I will probably live with this the rest of my life. I have seen doctors, including pain management. I tried gabapentin (300 mg three times daily), tramadol and Lyrica, with no help. Vicodin doesn’t relieve pain but does calm me. I have had two nerve blocks and used CBD. None helped. Also, I have tried all sorts of OTC ointments without relief. — P.S.

ANSWER: Shingles (the word comes from the Latin word for “belt or girdle,” cingulus) is a reactivation of the chickenpox virus from natural infection or, less commonly, from vaccination. It usually appears in a belt-like distribution over one half of the body. The virus travels down the nerve endings and causes a fluidfilled blister, which is contagious only to people who have never had chickenpox. The rash may be preceded by a period of itching or pain.

If the rash is recognized in time, treatment with antiviral medicine can reduce the likelihood of developing the complication you have, which is called post-herpetic neuralgia (PHN). Many people describe the pain as burning, but it can also be sharp and stabbing. It may be constant or intermittent, and variable in severity, all the way to excruciating. Light touch on the area can be painful.

The older a person is, the more likely she or he is to develop post-herpetic neuralgia, and the longer it may last. Without treatment, almost 20 percent of people over 70 years old will develop this complication. In people over 65, it lasted a mean of 3.3 years. There is still hope it will go away on its own.

Gabapentin is commonly used for treatment, but my experience is that it is hard to use, since the effective dose is much higher than you tried: 900 to 1,200 mg three times daily. Unfortunately, the medication causes so much sedation that many people cannot tolerate it, and my practice is to very slowly increase the medication dose over months. Other drugs that work on pain fibers, such as amitriptyline, also may be tried.

PHN is associated with profound problems, including depression, loss of function, loss of libido, poor sleep and loss of appetite with weight loss. I have seen people become bedbound during shingles from being unable to get out, and they rapidly lose muscle strength.

Because treatment for PHN is not very good, prevention is a high priority. The new shingles vaccine is excellent, but sadly, still in short supply.

DEAR DR. ROACH: Does cooking affect fiber content in foods? I find that I have an easier time eating cooked vegetables, but I have read a recommendation to eat raw vegetables for fiber. I cook them by steaming. — A.N.

ANSWER: Cooking does not significantly decrease the amount of fiber in foods. You can get the benefits of fiber from raw or cooked vegetables. Overcooking vegetables does reduce their vitamin content, but brief steaming doesn’t much affect the vitamins in food. Peeling vegetables reduces both fiber and vitamin content, so whenever possible, leave on the skin after a thorough scrubbing. Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med. cornell.edu or send mail to 628 Virginia Dr., Orlando, FL 32803.