DEAR DR. DONOHUE: I have been getting bimonthly testosterone injections for close to a year. I’ve noticed that my testicles are shrinking. Is this normal with testosterone replacement? What are the complications of this? Is there a drug that increases the natural production of testosterone? The reason for my injections was a low testosterone level. After three months of injections, my level was even lower. — P.P.

ANSWER: As a man grows older, his testosterone production decreases. Not all men suffer any great consequences from this. Those who do experience such things as a lowered sexual drive, a loss of energy, a reduction of muscle size, a decrease in red blood cell production and a loss of calcium from bones. Replacement therapy makes sense for men who have some of these consequences along with a low blood testosterone level.

Testosterone replacement leads to a reduction in testicle function. Testicle size decreases, but only after many years of treatment. The consequence of shrinkage isn’t a threat to health. It indicates that production of natural hormone is being taken over by the injected hormone. Supplemental testosterone might encourage growth of the prostate gland; the symptoms of this is difficulty in emptying the bladder. There’s a theoretical possibility that it could encourage the growth of prostate cancer. It often leads to breast enlargement. On the good side, it preserves muscle tissue and prevents osteoporosis.

How long after you started therapy was your testosterone level measured? If it was near the time of your next injection, I can understand why it was low. If the test was done within a week of getting an injection, I cannot explain its drop. Your doctor has to come up with an answer for that.

DEAR DR. DONOHUE: I had a recent heart scan, and the report refers to myocardial bridging. I would appreciate your explanation of that term. I am 82 and take no medicines. — A.P.

ANSWER: The main heart arteries — coronary arteries — run along the outside of the heart. Branches from those main arteries dip into the heart muscle to nourish it. Myocardial bridging indicates that one of the main heart arteries has burrowed into the muscle for a short distance. Usually this is a harmless condition that produces no symptoms. For a few people, it impairs blood flow through that segment of artery, and that, in turn, brings on chest pain.

You have had myocardial bridging for 82 years, from the day of your birth. It hasn’t caused you an iota of trouble. It won’t.

The booklet on heart artery disease explains the common illnesses affecting those vessels and how they lead to heart attacks. Readers can obtain a copy by writing: Dr. Donohue — No. 101, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order for $4.75 U.S./$6 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

DEAR DR. DONOHUE: My husband has to be fed via a PEG tube. He had been choking on food. The doctor explained that food gets into and sinks to the bottom of his lungs and causes pneumonia. He has a small diverticulum in his neck that cannot be corrected because of his age — 87. Is there an upside to all this? — D.S.

ANSWER: PEG is percutaneous endoscopic gastrostomy. The tube is introduced into the stomach by way of a scope (endoscopic) that has been passed into the stomach through the mouth. The doctor uncoils the tube, pushes it through the stomach (gastrostomy) and through the skin. When a person is clothed or wearing pajamas, the tube cannot be seen. The procedure takes only about 20 minutes and is not painful.

This is a wonderful advance for feeding people with swallowing problems. When your husband swallows, food and liquid get into his windpipe (trachea) and find their way into his lungs. Food in the lungs is an irritant that brings on pneumonia, lung inflammation. Germs that live in the mouth add to the lung inflammation. A PEG tube prevents this from happening. It’s a huge upside.

As your husband gains strength, his swallowing difficulties might disappear. If they don’t, the tube can be left in place for a fairly long time. It beats having to have a tube passed into the stomach through the nose.

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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