DEAR DR. DONOHUE: My doctor thinks I might have multiple sclerosis. All this started because I couldn’t see well out of my left eye. That has cleared without any treatment. I know very little about this illness, except that it leaves a person wheelchair-bound. I understand there is no treatment. I am 41 and have four children. I am devastated by all this. Please explain it to me. — G.S.

ANSWER: Multiple sclerosis gets its name because many (multiple) scars (sclerosis) appear in the brain and spinal cord. The scars come about due to a disruption in myelin, the insulating material for nerves. When myelin is lost, nerve transmission is interrupted. That’s the basis for all the symptoms of MS. It’s believed that antibodies attack myelin. What turns on the production of these antibodies remains unknown.

Often, the first sign of MS is a vision disturbance such as the development of a blind spot in one eye. Weakness of an arm or leg, a staggering walk, numbness in a body region, sensitivity to heat with a worsening of symptoms and outright pain in a particular area are some of the signs of this illness. Almost as a rule, the initial signs and symptoms disappear. For the diagnosis, a return of different symptoms points to MS.

MRI scans show the brain and spinal cord scars with great clarity. Changes in spinal fluid add evidence to the diagnosis.

The most common kind of MS is relapsing-remitting MS. Symptoms go but are followed by a new outbreak of different symptoms. In time, the symptoms can become permanent.

About 350,000 people in the United States have this illness. Women patients outnumber men by a factor of 3 to 1. Peculiarly, geography has a great influence. People who live in northern climates are more likely to come down with it than are those who live in southern climates. The illness most commonly appears between the ages of 20 and 50.

Treatment is available. We’re jumping the gun in talking about it since you have not been officially diagnosed as having it. Bear in mind that treatment has made this illness not as hopeless as you imagine.

DEAR DR. DONOHUE: My visit to my brother and his family in New Mexico was ruined by the bite of a brown recluse spider, a creature I have never heard of. I was wakened from sleep with pain in the back of my left arm. The pain got worse. I showed my brother my arm, and he said it was a spider bite. I saw a local doctor, and he confirmed the diagnosis. The doctor put me on a medicine. Are there any future consequences of this? — L.P.

ANSWER: The brown recluse spider is reclusive. It likes dark, quiet places: basements, attics, closets, woodpiles, under the bark of dead trees and under rocks.

These spiders are small, less than two-fifths of an inch. They’re brown and have a violin-shaped mark on their back. They’re distinctive among spiders because they have six eyes — one pair in the middle of the head and a pair off to both sides. Most spiders have eight eyes, two rows of four pairs.

Their bite causes a burning sensation, which intensifies during the next two to eight hours. Usually, all heals in a week. In a small number of people, a black scab forms, which becomes an open ulcer. You probably were put on dapsone to prevent that from happening. No future consequences lie in store for you.

DEAR DR. DONOHUE: Is it safe to reuse coffee? My husband makes a big pot one day and puts what’s left in a container and refrigerates it. I’ve been told this isn’t healthy. Why? We’ve done this for 25 years. — E.F.

ANSWER: There’s nothing unhealthy about saving coffee. It’ll be a bit stronger the next day because reheating it leads to a loss of some water. Coffee connoisseurs snub reheated coffee because its flavor doesn’t please their palates. It has no health implications.

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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