To Readers: A recent discussion of nighttime leg cramps brought an avalanche of readers’ remedies, as it always does. I can’t submit all for publication, but I’ll try to include more throughout the year in future columns. I also cannot vouch for their effectiveness. I am sure they aren’t harmful. Try them if you wish.

 A.S. says the use of an electric blanket stopped her cramps. Many readers suggest a teaspoon of apple-cider vinegar in the morning and again before going to bed. (It might wreak havoc on some people’s stomachs.) M.K. advises coenzyme Q-10 (found in drugstores and health-food stores). L.A. suggests putting on pure-wool socks before going to bed. W.Z. obtains total relief by abstaining from coffee and other caffeine-containing foods and drinks from noon on. Tums at bedtime works for M.B. and her husband. Tonic water is advised by a large number of readers. (Tonic water does contain quinine, which was a popular prevention until its over-the-counter sale was prohibited.) J.M. claims that pickle juice works. (Again, a word of caution to those with delicate stomachs.) N.H. says folic acid, a B vitamin, solved her cramping.

 Many suggest the very popular practice of putting a bar of soap between the sheets to eliminate nocturnal cramps. I have been aware of this remedy for many years, but skepticism keeps me from suggesting it in spite of widespread testimonials for its efficacy. Details vary. Some say any soap will do, wrapped or unwrapped. Others say laundry soap and not “wimpy, cosmetic soap” is the kind that works best. Where the soap is placed is another moot point. The most popular location is the foot of the bed. I am still a skeptic.

 Pinching the skin between the upper lip and the nose is a suggested way of promptly ending a cramp. I believe this does work. It works for me, anyway.

 The booklet on restless leg syndrome and leg cramps discusses these common miseries in detail. To obtain a copy, write: Dr. Donohue — No. 306, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.75 U.S./$6 Can. with the recipient’s printed name and address. Allow four weeks for delivery.

 DEAR DR. DONOHUE: When I read the letter of the 25-year-old man with undiagnosed chest pain, I thought of my brother, who died of arrhythmogenic right ventricular dysplasia. He had the same symptoms and was in his mid-30s. He died suddenly of this. It took the medical examiner four months to determine the cause of death. The letter writer should be aware of this. — P.G.

 ANSWER: I’ll bet not more than five readers have ever heard of ARVD, arrhythmogenic right ventricular dysplasia. It’s being recognized with greater frequency. It’s the cause of 10 percent of sudden deaths in those younger than 65.

 It’s a genetic disorder in which scarlike tissue and fat replace heart muscle in the right ventricle, the heart chamber that pumps blood to the lungs. It’s a stealthy illness with few symptoms. Nondescript chest pain, palpitations and fainting spells are warnings of it. Often, sudden death is the fate of undiagnosed cases. An EKG shows suggestive changes, and an echocardiogram (a soundwave picture of the heart) or an MRI scan provides substantial information. You’re right. The young letter writer ought to have his doctor consider this diagnosis. As it becomes better known, more people will be identified before the tragedy of an unexpected death occurs.

 DEAR DR. DONOHUE: Do arthritis and AIDS have the same symptoms? Is AIDS some kind of cancer? — Anon.

 ANSWER: AIDS is a viral infection with HIV, the human immunodeficiency virus. It is not a cancer, but the disruption of the immune system makes some patients disposed to develop some cancers.

 Arthritis is an illness involving joints. There are many kinds of arthritis — rheumatoid arthritis, osteoarthritis and gout are a few examples. A few AIDS patients develop joint pains, but the majority do not. Arthritis and AIDS are two quite different illnesses.

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, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com.

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