DEAR DR. DONOHUE: I have dry eyes. It’s very disturbing, because they have induced an increased tear production, and the tears interfere with my vision. I do use artificial tears, but they help only for a short while. Can you provide any advice? — F.Z.

ANSWER: It sounds contradictory to say that dry eyes cause watery eyes. But it’s true. Dry eyes shift the tear glands into high gear, and they produce torrents of tears. Treating the tearing hinges on finding the cause for your dry eyes.

Medicines sometimes are to blame. Drugs used for many digestive problems, some antidepressants, Parkinson’s disease medicines and sleeping pills are only a few of the drugs that dry the eyes.

Illnesses that do it include thyroid gland disorders, psoriasis, rosacea and Sjogren’s syndrome. You might not be familiar with Sjogren’s, but it’s not such a rare thing. It’s an immune attack on the tear glands, the salivary glands or both. When both are under attack, as they frequently are in this illness, the result is dry eyes and dry mouth.

You might try a different brand of artificial tears, or you could try artificial tears without any preservatives. Those kinds of tears are expensive. Restasis, a prescription medicine, often can lead to a satisfactory solution to the dry-eyes problem.

You can’t successfully treat this condition on your own. You need the help of an eye doctor to pinpoint the problem and suggest the best treatment for you. It could be that dry eyes aren’t the reason for your watery eyes. Perhaps you have an entirely different cause, such as a blocked tear duct. That duct drains tears from the eyes. A plugged duct doesn’t, and tears stream down the cheeks. An eye doctor often can unplug the duct with a simple office procedure.

DEAR DR. DONOHUE: My wife is 85 years old and suffers from dementia. Her short-term memory is completely gone. She takes Namenda and some other medicines.

Our friend’s son, who is a doctor, recommends Axona in addition to Namenda. My wife’s doctor doesn’t know much about it. Her New York doctor does not think it would be helpful.

We would appreciate hearing your thoughts on Axona. — J.B.

DEAR DR. DONOHUE: My mother has Alzheimer’s disease. I am greatly interested in the food supplement Axona, which is a new Alzheimer’s treatment. What do you think of it? — L.P.

ANSWER: Axona’s main ingredients are triglycerides, fat-like substances. The manufacturer states that Axona supplies Alzheimer’s patients with an alternate fuel for brain cell metabolism and can, thereby, improve the functioning of those with mild to moderate Alzheimer’s disease.

The product appears to be safe. I can’t vouch for its effectiveness. If you want to try it and the price is not prohibitive, you can do so. Don’t, however, expect a miraculous transformation. The Medical Letter, a respected journal that evaluates medicines, says about Axona that “its effectiveness remains to be established.” You know, don’t you, that it requires a prescription?

DEAR DR. DONOHUE: I went to give blood at the Red Cross. The receiving bottle had only an inch of blood and then bubbled. They finally stopped the procedure and said, “We are not going to get a pint from you.” My heartbeat is 58, and I read where it should be 60 to 100. Is that the reason I couldn’t produce a pint of blood? I am not athletic. What can I do to produce more blood? — J.A.

ANSWER: There’s nothing wrong with you. The needle or the tube inserted in your vein abutted against the vein wall. Blood couldn’t get through. A heartbeat of 58 is no danger if you have no symptoms, and you don’t.

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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