DEAR DR. GOTT: What would cause my eyelids to twitch? I asked my ophthalmologist the last time I visited him for a pressure test for glaucoma. He responded it could be stress or nerves. I'm not under stress, and my left eyelid has continued to twitch for weeks. 

My eye pressure has been controlled with Lumigan, with the only side effect being the skin around my eyes turning pink. But why the twitching?

DEAR READER: Eye twitching is an involuntary movement of the eyelid that can last for a few seconds, days, weeks or months. Generally speaking, it is harmless and will cease without treatment. In very rare instances, the twitch may be a sign of certain brain and nerve disorders. However, with these unusual conditions, there are accompanying signs and symptoms that come into play to direct a physician elsewhere. 

Your specialist was correct in thinking your eye twitching might have resulted from stress or nerves. Beyond that, smoking, a lack of sleep, physical exertion and the ingestion of alcohol and caffeine can prolong the twitch. 

You may have the answer to your dilemma. Your specialist prescribed Lumigan, an eye drop that treats elevated pressure in the eyeball caused by open-angle glaucoma. As a general rule, Lumigan is ordered after other remedies have failed to work. Perhaps your ophthalmologist tried several other sources initially and was unsuccessful in lowering the buildup of pressure. I say this because the drug carries several possible side effects including red eyelids, itchy and burning eyes, visual disturbances, blepharitis and more. I believe the Lumigan may be the cause of, or is contributing to, the annoying twitching you are experiencing. 

Return to your ophthalmologist to determine whether he agrees there could be a connection with the prolonged symptom and the medication he has you on. If so, perhaps another eye drop can be prescribed that will keep your pressure down and allow the twitch to stop. 

To provide related information, I am sending you a copy of my Health Report "Consumer Tips on Medicine." Other readers who would like a copy should send a self-addressed stamped No. 10 envelope and a check or money order for $2 to Newsletter, P.O. Box 167, Wickliffe, OH 44092. Be sure to mention the title. 

DEAR DR. GOTT: What is the difference between Grave's disease and hyperparathyroidism?

DEAR READER: Grave's disease is the most common cause of hyperthyroidism, which occurs when the immune system attacks the thyroid gland. This causes the gland to enlarge, resulting in the production of too much hormone. Symptoms of the condition include bulging eyeballs, rapid and irregular heartbeat, nervousness, irritability, tremor and more.

Treatment includes prescription beta blockers, antithyroid medication, radioactive iodine treatment and surgery. 

Now, on to hyperparathyroidism. There are four pea-sized parathyroid glands in the neck. The parathyroid glands secrete a substance that balance calcium and phosphorous in the body. When one or more of the glands become inappropriately overactive, too much parathyroid hormone results. The normal balance is interrupted, bones may lose calcium, too much calcium may be absorbed from food, calcium may increase in the urine, and kidney stones can result. 

Symptoms include aches and pains, depression, fatigue, nausea, constipation, increased thirst and urination, and impaired memory. Treatment is accomplished primarily through surgery to remove one or more of the enlarged glands. You should see a doctor for further advice.

To provide related information, I am sending you a copy of my Health Report "Thyroid Disorders." Other readers who would like a copy should send a self-addressed stamped No. 10 envelope and a check or money order for $2 to Newsletter, P.O. Box 167, Wickliffe, OH 44092. Be sure to mention the title. 

If readers would like to contact Dr. Gott, they may write him through your newspaper or send their mail directly to Dr. Gott c/o United Media, 200 Madison Ave., 4th fl., New York, NY 10016. However, if readers want to request a newsletter, they should write to the Ohio address.

Dr. Peter Gott is a retired physician and the author of the book "Dr. Gott's No Flour, No Sugar Diet," available at most chain and independent bookstores, and the recently published "Dr. Gott's No Flour, No Sugar Cookbook."

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