DEAR DR. DONOHUE: I have recently been diagnosed with neurocardiogenic syncope. Please explain to me what this is and if there is anything I can do to prevent it in the future. – C.W.

Syncope (SINK-uh-pea) is a faint. Neurocardiogenic syncope, also known as vasovagal syncope, is one kind of faint and probably the most common kind.

Faints happen when there’s a brief interruption of blood flow to the brain. When that happens, the brain goes blank and the person slumps to the floor. Such interruptions can come from abnormal heartbeats, from a too-narrow heart valve, from a transient drop in blood pressure, or even from a tight collar digging into the neck.

Neurocardiogenic syncope involves a nerve (neuro) and the heart (cardiogenic). One common situation where it happens is when a person stands immobile in one spot too long. Blood doesn’t get back to the heart, and that means that too little blood reaches the brain. In such circumstances, the body has sensors that detect that these things are happening and takes immediate corrective action. However, sometimes those sensors fail and the wrong messages reach the brain, which then sets in motion action that really messes everything up. The heart slows down – just the opposite of what it should do. A heart nerve, the vagal nerve, brings that message to the heart. This is the kind of faint that happens in hot rooms, in a frightening scene or under emotionally charged circumstances. Most of the time there is no health implication, but it does require that a doctor states all is well with the heart and brain.

You can prevent this kind of faint by sitting or lying down at the first inkling that it is coming on. You can also stave it off by forcefully contracting as many muscles as you can – legs, stomach, arms – and holding them contracted for a good while.

When fainting episodes are frequent, then medicines can be prescribed to stop them.

DEAR DR. DONOHUE: Does a bladder have brains? If it doesn’t, how come it knows when exactly two hours are up to signal me that I have to get out of bed to empty it? I pass a good amount of urine each time I go. Where does it all come from? – J.

These are rough numbers. A normal bladder holds a little less than 1 pint of fluid (about 450 ml). People make around 2 quarts of urine in 24 hours. Most people, therefore, can get by with four trips to the bathroom in 24 hours, not counting trips for solid waste. Younger people produce more urine during the day; older people, more at night. That’s one reason older people have to get up during sleep, but it should not be every two hours.

If you really are urinating great volumes of urine in 24 hours, then you have to think of such things as sugar diabetes and pituitary-gland malfunctions – unless, of course, you drink prodigious amounts of fluid. Buy a cheap, plastic bottle with volume measurements printed on its side and measure how much urine you produce in one day to see if your nocturnal trips are a matter of overproduction.

I bet your problem is an enlarged prostate gland. A large gland makes it impossible to completely empty the bladder. The bladder is partially filled all the time, so it takes only a short time between voidings for it to totally fill again. And this is particularly so at night.

DEAR DR. DONOHUE: My granddaughter was diagnosed with Williams syndrome at age 3, not by a specialist. She believes she’s infertile because of the syndrome. Is she? – J.D.

Children with Williams syndrome are missing a small part of a chromosome. Chromosomes are long chains of genes. Some of the signs of this syndrome are a small jaw, upturned nose, small teeth, a bow-shaped upper lip and round, full cheeks, giving the child the appearance of an elf. They can also have heart and blood-vessel problems. Schoolwork might be difficult.

Unless your granddaughter had genetic studies done at age 3, I would seriously question if she has Williams syndrome. Furthermore, I don’t find infertility listed as part of the picture.

DEAR DR. DONOHUE: I had a small, painless sore on my genital skin. The doctor said it was herpes. I have been faithfully married to my husband for 16 years, and I believe he has been faithful to me. How could this happen? – R.T.

One possible explanation is misdiagnosis. A first outbreak of herpes often comes with fever, headache and muscle aches. You had none of those symptoms, did you? The outbreak starts as tiny blisters in one or more patches. They merge and form a shallow sore. The pain is quite significant. None of this sounds like what you had.

How did the doctor make the diagnosis? Was it only by looking at the sore? If it was, then I doubt the diagnosis was correct.

If the sore heals and if you never have another outbreak, it’s most unlikely that you had herpes. If you do have a recurrence, see another doctor and ask for some diagnostic tests, like a scraping of the sore for microscopic confirmation or for a culture of the sore for herpes virus.

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

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