DEAR DR. DONOHUE: I am 13 years old and would like you to say something about hypoglycemia. My mom believes we both have it. Whenever I haven’t eaten for a while, I get headaches, stomachaches and nausea. I also feel very warm, weak and shaky. Eating sugary foods makes it worse. I also get nervous easily. My blood sugar levels have been checked, and diabetes is not indicated. What would you recommend? – M.P.

ANSWER: Low blood sugar – hypoglycemia – produces many of the symptoms you describe: trembling, sweating, nausea, dizziness, headache and confusion. The trouble is that many other things produce the same symptoms – anxiety, for example.

The proof that hypoglycemia is the cause demands that three rules be observed: hypoglycemia symptoms appear, the blood sugar at the time the symptoms appear is below 50 to 60 mg/dL (2.8 to 3.3 mmol/L), and the symptoms go away when blood sugar returns to normal. How do people get their blood sugar checked when symptoms occur randomly? Your doctor can show you how to use a glucometer, a simple instrument that diabetics use to check their blood sugar. And he or she might let you borrow a meter for a while. Or the doctor can have you blot a drop of blood onto special paper that can be tested for sugar at a later time. Or you can carry with you a lab request from the doctor so you can rush to the lab when symptoms strike.

The most important but rare cause of hypoglycemia is a tumor of the pancreas that pours out too much insulin. It’s diagnosed by measuring blood sugar after a person has been on a supervised fast for 48 to 72 hours.

More commonly, hypoglycemia comes on two to four hours after eating and is due to a slight glitch in turning off insulin release when blood sugar begins to drop. If this kind of low blood sugar is diagnosed, frequent, small meals can often control it. Try eating some fruit or drinking fruit juice when you have an attack. Either should get rid of a hypoglycemic spell.

DEAR DR. DONOHUE: In one of your columns, you reported that a new study on saw palmetto found it ineffective for enlarged prostate glands. I saw it after just having had saw palmetto prescribed for me. You did not mention the source of the study, how many men were involved or the duration of the study, let alone the dose administered or the degree of gland enlargement. Would you provide that information? – E.M.

ANSWER: Sure, I’ll do that. Saw palmetto is a product of a palm tree that has been used by more than 2 million men for enlarged prostate glands, and many have been quite happy with it.

The study I cited appeared in the Feb. 9, 2006, issue of the New England Journal of Medicine. The lead author is Stephen Bent from the University of California, San Francisco. The number of men taking part in the trial was 222, all of whom had moderate to severe enlargement. The dose of saw palmetto was 160 mg, twice daily, and the medicine was taken for a full year. The conclusion of the study is: “In this study, saw palmetto did not improve symptoms or objective measures of benign prostatic hyperplasia.” Prostatic hyperplasia is gland enlargement.

The booklet on the prostate gland deals with gland enlargement and cancer. Readers can order a copy by writing: Dr. Donohue – No. 1001, 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: I’m a healthy 74-year-old woman on no medicines. My blood count has shown consistent abnormalities for two years, and it is worrisome to me. My concerns are leukemia or myeloma. What is your opinion? – M.P.

ANSWER: Your white blood count is a little low, but not so far off the mark as to indicate any illness. Your red blood cell count is a trifle low too, but not low enough to constitute anemia. None of your values raise an eyebrow. None indicates leukemia or myeloma.

DEAR DR. DONOHUE: My 47-year-old son has had CIDP for one year. Can you give me information on its cause and cure? Doctors have given him IVIG infusions, yet he still doesn’t feel well. – R.M.

ANSWER: Only a handful of people have ever heard of CIDP, chronic inflammatory demyelinating polyneuropathy, yet it is a relatively common but underdiagnosed condition. Myelin is the insulating material wrapped around nerves. Without myelin, nerves are short-circuited. People’s sensation is impaired. Muscles are weakened. Affected patients stumble when walking and find they cannot hold on to things as they once did.

The immune system has made antibodies that attack the myelin covering of nerves, and it crumbles off. Blocking the effect of these antibodies is the basis for the treatment of CIDP. Intravenous gamma globulin, IVIG, is one standard treatment. It didn’t work for your son, but it does for many. Prednisone, one of the cortisone drugs, fights the inflammation induced by the antibodies and can preserve nerve insulation. Drugs that target the immune system directly are other therapeutic options. Such drugs include cyclosporine, cyclophosphamide and methotrexate.

In time, most people experience improvement in their CIDP symptoms. Years after its onset, about 75 percent are much better and much more active. Death due to this illness is most uncommon.

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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