DEAR DR. DONOHUE: I have a question that I have been puzzling over for some time, and I would love your opinion on it. I have known many people who were on prednisone. At first it is a wonder drug, and they feel fine. After they are on it for some time, problems and side effects start to appear.

Why is this drug prescribed so often? Are there alternatives? I feel like I should wear a bracelet that states never to give me prednisone. — M.J.

ANSWER: Prednisone is one of the drugs in the large cortisone family of drugs. I will use cortisone as the name for the entire family so not to confuse readers. Prednisone happens to be the most prescribed cortisone drug.

Our adrenal glands make cortisone for us. Without it, life would not go on. It helps in the processing of fats, proteins and carbohydrates. It’s involved in the immune system. It has a powerful effect on suppressing harmful inflammation.

The flip side to cortisone drugs is that high doses used for prolonged periods can cause big troubles. Cortisone increases sugar production within the body and can lead to diabetes. It breaks down protein and thereby weakens muscles. It redistributes fat. Fat leaves the arms and legs and deposits in the face and trunk. Cortisone makes a person more susceptible to infections. It can bring about cataracts. It also can lead to osteoporosis. For lethal illnesses that cannot be controlled by any other medicines, high doses of cortisone have to be given to preserve life. In those instances, the side effects of the drug must be tolerated. Doctors always try to lower the cortisone dose once symptoms of the illness under treatment begin to lessen.

Doctors are aware of the potential side effects of cortisone. Not only do they weigh the pros and cons of high doses, but they also prescribe medicines that keep in check many of cortisone’s unwanted side effects. Your bracelet should say: Give me prednisone whenever it will save my life.

DEAR DR. DONOHUE: Enclosed find copies of my recent blood tests.

I am a 68-year-old woman and never had a weight or blood pressure problem. Nine years ago I had a rapid heartbeat diagnosed as atrial fibrillation and had ablation therapy for it.

I walk two miles every day and eat a balanced diet. My weight is 123 pounds. I take a number of vitamins and minerals and have taken them for 16 years.

My doctor hasn’t made any comment about the high vitamin B-12 level on my blood tests. Last year, it was normal. Can you tell me the cause? — R.E.

ANSWER: Your elevated blood level of vitamin B-12 has to come from food or from your supplements. Our bodies do not make it. The main food sources of B-12 are meat, fish and dairy products. I don’t know the vitamin B-12 content of your supplements, but you can get that information from their labels. The recommended daily allowance is 2.4 micrograms.

You don’t have to worry about your blood level of this vitamin. No adverse effects come from excess B-12. All the same, you don’t need to take more than the recommended dose. You can save yourself some money.

DEAR DR. DONOHUE: I recently read several articles about the use of food-grade hydrogen peroxide. I am interested in using it for prostate and urinary tract problems. Are there real benefits from it? — J.C.

ANSWER: Concentrations of 1.5 percent hydrogen peroxide are used by some as a mouthwash and at 1.5 percent to 3 percent as a wound cleaner. The same doses are used to remove wax from the ear canal.

I can’t find any confirmation of the benefit of using food-grade hydrogen peroxide for prostate or urinary tract problems. I would not encourage you to use it. Food grade is a very high concentration.

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.