DEAR DR. DONOHUE: Please discuss Lewy body disease more fully than I have seen you do in past references to it. My wife has been diagnosed with this disease. I am told that it is a combination of Parkinson’s disease and Alzheimer’s disease. What is the outlook? – W.S.

ANSWER: Many illnesses fall into the category of dementia. Dementia is a marked deterioration of mental functions. Memory disappears. The ability to learn new material is lost. Simple day-to-day tasks like writing a check are impossible chores.

The largest percentage of dementia patients have Alzheimer’s disease, but close behind it is Lewy body disease.

The dementia of Lewy body disease has a few distinguishing characteristics. For one, it can be episodic. A person can be mentally at sea one day and then be lucid the next. As the months and years pass, however, periods of lucidity are fewer and fewer. Hallucinations are another of its trademarks. Patients see things that are not there. The imaginary sightings are usually people or pets.

Symptoms of Parkinson’s disease complete the picture. Lewy body patients can have the slowness of movement so typical of Parkinson’s disease. Rigid muscles, another Parkinson’s feature, are also seen. Patients might or might not have a Parkinson’s tremor.

Drugs used for Parkinson’s disease are also used for Lewy body disease. Those drugs include Aricept, Reminyl and Exelon.

If a Lewy body patient hallucinates, then medicines used for hallucinations are prescribed. However, Lewy body patients are very sensitive to these medicines, and it is good to have the opinion and monitoring of a doctor experienced in treating this illness.

Outlook? A patient with the disease may last months or 10 or more years. Treatment is difficult.

DEAR DR. DONOHUE: I have a sister who is 10 years younger than I am. She is 23. She is currently taking epilepsy medicine. She had a few seizures. What causes epilepsy? What are my chances of coming down with it? Does it shorten life? – J.G.

ANSWER: There are many different kinds of epilepsy, and there are many different causes of it. An old head injury could cause a brain scar. That scar, later on, can be the switch that turns on an electric storm within the brain that results in a seizure. Brain infections are another cause. Brain tumors, brain malformations and malformations of blood vessels within the brain are other causes.

For many, however, a definite cause goes unidentified. Genes certainly can play a role. Do not take that to mean that you are going to have epilepsy because your sister has it. Your chances of having it are not great.

A seizure follows a sudden and intense discharge of the brain’s electric energy. Medicines can often eliminate those electric discharges or, at least, keep them to a minimum.

If epilepsy shortens life, it is a minimal shortening. Most patients live a normal life span.

DEAR DR. DONOHUE: How long can you keep medicines? I have a drawer filled with unused medicines. The antibiotics I save I use on my children when they have a cold or get sick – I have five children. – H.I

ANSWER: Pharmaceutical companies generally state that medicines are good for one year. After that they should be discarded.

Can I put in a plug for you to stop saving antibiotics? It’s dangerous to give antibiotics to children without knowing the definite diagnosis of what they have. You can induce an allergy to that antibiotic, and then it is not available when it is really needed.

Moreover, indiscriminate use of antibiotics encourages the development of bacteria that are resistant to antibiotics. You’re doing the public a disservice in handing out antibiotics.

Antibiotics are not treatments for colds. Colds are caused by viruses. Antibiotics do not touch viral infections.

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.