DEAR DR. DONOHUE: My husband and I always assumed our son was sensitive to penicillin - until recently, that is. He had occasion to get penicillin at camp this summer without knowledge of the previous reaction he had. Fortunately, there was no reaction this time. Why not? I thought once sensitive, always sensitive. We are happy, but confused. - Mrs. H.I.
ANSWER: Such sensitivity can be tricky. It is true that a very small number of people who seem to have been sensitive to penicillin in the past turn out not to be.We aren't sure why this is so. The sensible approach thereafter is to assume sensitivity and inform health care providers of that fact. If in the future there is need for antibiotics, an alternative one can be used. Or highly reliably skin tests for penicillin sensitivity can be done to make certain of the person's status.
DEAR DR. DONOHUE: Maybe this is a dumb question, but here goes. What is the difference between menopause and post-menopause? Is not menopause the end of periods? So what is post-menopause? - B.B.
ANSWER: Menopause is the phase in a woman's middle years when her normal monthly cycles begin changing. That is, periods become fewer, briefer and sparser. Post-menopause is the end of this decline phase, usually measured from the point where the woman has been totally menstruation free for a full year. For more, see the menopause booklet. Write to Dr. Donohue/No.21, P.O. Box 19660, Irvine, CA 92713- 0660, enclosing a long, stamped, self-addressed envelope and $1.
DEAR DR. DONOHUE: Can an overactive thyroid gland cause a person to have a very high cholesterol reading? - M.H.
ANSWER: Let me try to reconstruct your situation. Your thyroid gland was overactive, producing excess amounts of its hormones. That causes a speedup of metabolism, and that can keep cholesterol levels low. Then you got radioactive iodine. That destroys thyroid gland tissue (the goal). But it could make you hypothyroid with a resulting drop in thyroid hormones in your blood. Cholesterol levels rise with low thyroid hormone levels.
I am sure your doctor is now assessing things and checking your thyroid hormone and cholesterol levels. If necessary, he will raise the dose of thyroid medicine to bring your cholesterol down. Keep in touch with him.
DEAR DR. DONOHUE: Is there any physical benefit in donating blood? I have been a donor for years and have been extra healthy, it seems. Is it a healthy thing to do? - C.G.
ANSWER: The physical health benefit is for the people who are in dire need of that blood, and there are always more of them than there are donors.
Only in certain illnesses, such as ones involving iron overload, is bloodletting part of treatment. The notion that giving blood periodically is physically beneficial to the donor has no validity. Neither is there any harm from it.
DEAR DR. DONOHUE: Is it possible to have a skin rash after use of the nicotine gum, which I am using to try to kick the cigarette habit? - U.L.
ANSWER: There have been a few reports of this happening. If it does, stopping the gum ends the problem.
DEAR DR. DONOHUE: I am a female, 25, whose periods have stopped. One doctor said I needed to reduce. Another doctor did ultrasound and said it showed a few cysts on my ovaries. She was not impressed. Do a few cysts constitute polycystic ovary disease (which you discussed recently)? If not, how many do? - Mrs. C.M.B.
ANSWER: Polycystic means many cysts, but just how many is "many" has not been established. I have seen the figure 20 mentioned. But cyst numbers are less important than finding their cause and the cause of your lack of periods. The two can be linked.
An imbalance of pituitary gland hormones causes ovary cysts by throwing off ovarian estrogen production and altering the ripening time of eggs in the follicles. The hormones can be measured by blood tests.
More than ovary cysts are involved in saying someone has polycystic ovary disease. The woman does have a lack of periods, but she also may have hair on the face and chest and is often overweight. You fit that description well enough to perhaps have the problem, also known as Stein-Leventhal syndrome.
But even this is not the whole story. The problem may also lie in the adrenal glands, with improper production of both male and female hormones there. You need to find a doctor (gynecologist or endocrinologist) and allow time for a careful step-by-step investigation into all the numerous factors. If you have polycystic ovary disease, be assured that today it can be treated successfully.
- Dr. Donohue welcomes reader mail but regrets that, due to the tremendous volume received daily, he is unable to answer individual letters. Readers' questions are incorporated whenever possible.