DEAR DR. DONOHUE: My husband recently died from the effects of Lewy body disease. A sister of a friend in Florida died from it too. You’ve mentioned it, but didn’t expand on it. I wonder if you would. Few people have heard of it, and I’ve taken on the task of spreading information. – S.D.

Lewy body disease isn’t a rarity. It is second to Alzheimer’s disease on the list of causes for dementia – dementia being impaired thinking, mental confusion and memory loss. It was described in the 1960s, and that makes it an infant in the catalog of diseases. Lewy bodies are blobs of peculiar inclusions found in the brain cells of those with the illness. Dr. Lewy was an American neurologist.

Lewy body disease, in addition to the signs of dementia, has some unique characteristics. Patients’ mental confusion and memory deficits can clear for a time, but they always sink back into dementia’s confusion. They frequently suffer from visual hallucinations, seeing things that aren’t there. They stare for an inordinate amount of time. Daytime drowsiness is common. Disturbing nightmares in the early stages of sleep habitually recur. They also suffer from symptoms similar to those of Parkinson’s disease, such as a hand tremor.

No medicine cures Lewy body disease. A few medicines can relieve some of the symptoms. Clonazepam, for example, can decrease the number of nightmares. Parkinson’s drugs are helpful for the tremor. Alzheimer’s medicines are somewhat useful for dementia symptoms. None, however, is considered a breakthrough.

DEAR DR. DONOHUE: I am a fellow of almost 19 years. I have a urinary infection. I also have weak bladder muscles and lose control of urine. Is there an exercise for this? – S.M.

If your loss of urine control stems from a bladder infection – and it can do so – the resolution of the problem comes with an attack on the urinary infection. Antibiotics are the answer.

If you have a loss of control when you don’t have a urinary tract infection, please write back with details.

Exercise can be helpful for some varieties of incontinence – the loss of urine control.

DEAR DR. DONOHUE: Please answer a discussion we have had concerning gallstones. I know you can pass kidney stones in the urine, but can you also pass gallstones? – B.C.

Gallstones can pass through the bile duct into the small intestine and then be carried out of the body with undigested food. For this to happen, the stones have to be small.

Most of the time, gallstones are too large to pass through the bile duct, and it is these larger stones that lead to gallbladder attacks.

DEAR DR. DONOHUE: Will you explain what cold thyroid nodules are? My husband recently had his thyroid biopsied due to a cold nodule. He has no symptoms. His endocrinologist recommends that he get his thyroid removed based on the enclosed report.

It seems to me that the risk of surgery outweighs any benefits that may come from this surgery. My husband is 61.

What do you think of forgoing surgery and getting the thyroid checked every six to 12 months? – J.T.

A cold nodule on a thyroid scan is very suggestive of thyroid cancer. “Cold” means it doesn’t light up like the rest of the gland when a radioactive element is given to scan the gland.

The report you sent is a pathologist’s report on a needle biopsy of the cold nodule. A biopsy is the next step taken when a person has a cold nodule. The pathologist cannot distinguish between thyroid cancer and a benign thyroid growth.

In situations like that, surgery is strongly suggested. If an error is to be made, the error should be on the safe side. Removing an early thyroid cancer almost assures cure. Letting one go can make cure difficult or impossible. I side with the endocrinologist.

DEAR DR. DONOHUE: I take Lotrel for my blood pressure. The pharmaceutical information states that I should not take potassium with this medicine. I also take daily furosemide. Because of that, my doctor says I should take a potassium supplement. What am I do to about this quandary? — J.R.

Lotrel is a combination drug, containing amlodipine, a calcium-channel blocker, and benazepril, an ACE inhibitor. Both lower blood pressure, but each has a different way of doing so. ACE inhibitors raise blood potassium levels in some users, so potassium supplements are avoided when taking them.

You, however, also take furosemide, a water pill, which causes potassium loss in the urine. That offsets the possible rise in blood potassium from the ACE inhibitor.

If your doctor believes you need a potassium supplement, take it. Get your blood potassium checked in about a month. If it’s normal, continue with the supplement. If it’s high, stop it.

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