DEAR DR. DONOHUE: Do you actually answer readers’ questions, or do you have writers come up with the questions? I have written to you many times about an illness called relapsing polychondritis, which most people and many doctors have never heard of. My late wife was a victim of it. I also wrote asking if carbonation is bad for the kidneys. I would appreciate answers. – R.L.

ANSWER: The answers are to readers’ questions. I just proved it to you – I am answering yours.

Relapsing polychondritis is not terribly common, but it’s not terribly rare either. It usually begins in a person’s 40s or 50s. You might recognize the “chond” in it as signifying “cartilage.” It is recurring attacks of cartilage inflammation that mainly target the ears, nose and breathing tubes. Only in a few patients are all three sites involved.

The ears turn bright-red, become hot, swell and are tender and painful. How long an attack lasts is unpredictable. The earlobe is never involved because it has no cartilage.

With the nose, the cartilage that separates the right and left nostrils is assaulted. The nose runs. Crusts form on its insides. It often bleeds. In time, the nose can cave inward and look much like a horse’s saddle.

When the airways are part of the picture, coughing, shortness of breath and hoarseness result.

Sometimes other cartilage-containing tissues – the eyes, the inner ear and joints – are involved.

Polychondritis is believed to be an illness brought on by an immune system gone amok. Medicines like azathioprine and methotrexate dampen the immune system’s destruction. During a flare-up, doctors usually prescribe cortisone drugs.

Carbonation doesn’t hurt the kidneys. If it does, mine are shot.

DEAR DR. DONOHUE: My glucose (blood sugar) monitor says to check for ketones when my blood sugar is high. But it doesn’t say what ketones are or how to check for them. Please explain. – M.P.

ANSWER: When fat is the main source of energy, ketones form.

The problem in diabetes is the inability of blood sugar – glucose – to penetrate cells. Sugar is the cells’ main energy source. Prolonged deprivation of sugar from cells makes them turn to fat for energy. A byproduct of fat-burning is ketones. Fat-burning takes place only when blood sugar levels are high and have been high for quite some time.

You can detect ketones both in blood and urine. Special paper strips are available that can be dipped into urine. Color changes occur on the paper when ketones are present. There are also tablets that detect ketones when urine or blood is dripped on them.

If your blood sugar is quite high and has been high for some time, it’s is more sensible for you to contact your doctor rather than checking yourself for ketones.

The diabetes booklet offers information on this illness and its treatment. People can order a copy by writing: Dr. Donohue – No. 402, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.75 U.S./$6.75 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

DEAR DR. DONOHUE: Please settle a dispute. How long does it take nicotine to leave the body? My husband says four days; I say one week. Who is right? – B.B.

ANSWER: It takes from three to 10 days for nicotine to leave the body. The time depends on the number of cigarettes a person smokes in a given period of time. With a light or moderate smoker, nicotine is gone in days. With a heavy smoker, it takes a week or more.

The half-life of nicotine in the body is 17 hours. That means half is gone in 17 hours, and then half of that amount is gone in another 17 hours, and on and on until what’s left is so small that tests cannot detect it.

DEAR DR. DONOHUE: What’s the recommended amount of zinc a person should take daily? I understand it’s necessary for prostate gland health. I am only 36, but I wonder, if I begin taking it now, will I not have prostate problems when I’m older? – T.T.

ANSWER: No one is positive that zinc has a huge influence on prostate gland health. A little while ago, there was talk that too much zinc might be a contributing cause for prostate cancer, but that information has been seriously challenged.

Taking zinc at your age is not going to protect you from future prostate troubles. Take the recommended daily allowance, which is 11 milligrams for men (8 for women). Do you appreciate how little a milligram is? One gram is close to one-thirteenth of an ounce. If a restaurant served you 1 gram of steak, you’d have a hard time finding it on your plate. A milligram is one thousandth of a gram. That’s microscopic size.

For some people, doctors advise doses higher than the recommended dose. For macular degeneration, for example, some doctors have their patients take high doses of zinc along with certain vitamins.

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

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