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On call: Excessive sweating

On call

Excessive sweating

Q. I am a 71-year-old man with diabetes and high blood pressure. I take Glucophage for my diabetes and Zestril for my blood pressure, and my doctor says both problems are under good control, but I’ve developed a very annoying problem. Every time I eat, I develop terrible sweating on my face and neck. It only lasts 10–15 minutes, but my shirt collar gets soaked and I’m too embarrassed to go out to dinner. Am I allergic to something in food? Am I getting hot flashes as my wife did when she had the change of life?

A. It sounds as though you really are taking very good care of yourself, and your doctor has prescribed a good pair of medications. Neither your lifestyle nor your medication is likely to be causing your problem. And although men who take hormones for prostate cancer can develop hot flashes, other men do not. Unexplained or excessive sweating can be a sign of low blood sugar (hypoglycemia), which is always a concern for diabetics. But your symptoms come on with meals, when your blood sugar should be rising. And although most medication used to treat diabetes can cause hypoglycemia, Glucophage (metformin) does not have this side effect.

Food allergies are also unlikely. Some people sweat excessively after they eat highly spiced foods, but since you seem to sweat at every meal, it would be hard to implicate a single food or ingredient.

If health habits, medication, hypoglycemia, and allergies are not to blame, what is? Your problem sounds typical for diabetic gustatory diaphoresis, which is medical jargon for exactly your complaint: profuse sweating (diaphoresis) triggered by eating (gustatory). But although the condition has a name, its exact cause is not known. Scientists know that diabetes can injure nerves (diabetic neuropathy), and they suspect that damage to parasympathetic nerves in the head, neck, and mouth may account for the problem.

Even if doctors don’t fully understand this problem, they can usually prescribe an effective therapy. Anticholinergicmedications counter the effects of the parasympathetic nervous system, thus reducing sweating. Examples include oxybutynin (Ditropan), which is ordinarily used for bladder spasms and certain types of urinary incontinence, and various antihistamines and tricyclicantidepressants. Unfortunately, all these medications can interfere with bladder emptying in men with benignprostatichyperplasia (BPH); they can also trigger attacks of angle-closure glaucoma, and they can produce excessive dryness in the mouth. Fortunately, though, there may be an alternative. Although it’s been tested in only a few diabetic patients, a 0.5% solution of glycopryrrolatelotion applied to the skin of the forehead and face (but not the mouth and eyes) once a day appears very effective. However, the drug is commercially available only in tablet form (Robinul) for the treatment of intestinal cramps or as an injection that’s ordinarily given before anesthesia, so your doctor and pharmacist would have to make special arrangements to prepare a solution for you.

Last updated:	August 21, 2006