DEAR DR. DONOHUE: I have been diagnosed as having labyrinthitis. My medical book says this is a viral infection of the inner ear. My symptoms include profuse sweating, dizziness and nausea. What is its treatment? – E.H.

DEAR DR. DONOHUE: I suffer from vertigo and take Antivert. I saw a neurologist, who recommended a patch used for motion sickness. What is the best medication to use? – D.L.

ANSWER: There are more than 17 conditions that cause dizziness (vertigo). I have to limit my remarks to the more common causes.

The inner ear is the body’s gyroscope, keeping it oriented regarding its location in space. When anything throws the inner ear off kilter, the result is dizziness.

Labyrinthitis is usually a viral infection of the inner ear. Most viral inner ear infections run their course within three weeks. Some people have to put up with them for longer periods, but almost all have a resolution of symptoms. Antivert is an oral medicine that can subdue dizziness. The patch to which D.L. refers is Transderm Scop. It is worn behind the ear, and its principal purpose is prevention and treatment of seasickness. Seasickness comes from the violent disturbance that a pounding sea inflicts on the inner ear. Many forms of inner ear disturbances result from a similar kind of inner ear perturbation. The patch, therefore, comes in handy for those conditions.

Benign positional vertigo is dizziness that comes on when people move their heads, like rolling over in bed or looking upward. Crystals in the inner ear have migrated to places where they should not be, and the displaced crystals set in motion an episode of dizziness. A doctor, using prescribed head movements, can often coax those crystals to return to the place where they belong.

This is such a superficial treatment of a complicated subject that I am embarrassed. Readers can learn more about dizziness in the newly published pamphlet on that problem. Write to: Dr. Donohue – No. 801, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.50 U.S./$6.50 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

DEAR DR. DONOHUE: My brother is in his 70s. When he drinks beer (he will sometimes have six bottles at a sitting), he pours about ½ teaspoon of salt into each beer. He does not have high blood pressure, and he believes this amount of salt does no harm to his body. He carries extra weight around his waist. Your comments, please. – Anon.

ANSWER: Some people are not sensitive to salt’s effect on raising blood pressure. Your brother might be one of them.

However, even though he does not now have high blood pressure, excessive salt retains fluid in the body. No one needs that, and no one is immune to that property of salt. With all the salt your brother uses, he could develop ankle swelling. Fluid – beer in particular – might also account for the extra weight he carries on his waist. He really should retire his saltshaker.

I don’t mean to poke my nose into other people’s business, but your brother drinks too much beer. It can have a more devastating effect on his health than salt does.

DEAR DR. DONOHUE: I am driving my husband crazy. I spend enormous amounts of time straightening the fringes on our rugs. We have been late for many engagements because of this habit of mine. My husband says it’s a mental illness. Could it be? – R.H.

ANSWER: You have obsessive-compulsive disorder. An obsession is a subconscious idea or memory that engenders anxiety. The compulsion is a stereotyped ritual a person adopts to eliminate anxiety. Constant hand-washing and fringe-straightening are two good examples. It is a mental illness, and it can be treated with medicine and professional counseling. Ask your family doctor about this.

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.