DEAR DR. DONOHUE: I have been hoping someone would ask you about my condition, leukopenia. I had numerous blood tests this past summer. My latest one indicates that I have a white blood count of 3,100. I am 61, weigh 138 pounds and am 5 feet 4 inches tall. I exercise daily, mostly by walking. I am a vegetarian who eats dairy products. My chief complaint is fatigue. Until recently, I was a restaurant manager working 60-some hours a week. Now I am semiretired.

My primary-care doctor says I should not worry, but I do. What do you have to say? — D.R.

ANSWER: Leukopenia is a low white blood cell count. In itself, it doesn’t usually produce fatigue. White blood cells are the body’s Armed Forces, keeping infections from occurring. A low count can lead to repeated infections. The normal white blood cell count is 4,500 to 11,000. Your count is on the low side, but it’s not so low that it constitutes a health danger to you. It’s unlikely to be the cause of your fatigue, and, since you have no obvious consequences from such a count, launching an intensive investigation at this point would not be rewarding.

Fatigue is a complaint that brings an enormous number of visits to doctors annually. A shortened list of the causes of fatigue includes anemia, hidden infections like TB, celiac disease, inflammatory bowel disease, diabetes, chronic fatigue syndrome, insomnia, sleep apnea, rheumatoid arthritis, lupus and depression. Stress and an underactive thyroid gland are two possibilities worth investigating. The change from a 60-hour work week to semiretirement paradoxically might have upset your equilibrium. Thyroid disorders can escape detection unless a few simple lab tests are done. I would recommend that you have such tests.

If you haven’t had a complete physical exam in some time, I would also recommend that you have one now.

DEAR DR. DONOHUE: Is there any remedy for a hammertoe other than surgery? I wear the correct size shoe. There was a time when I could wait two months before seeing the doctor to have the hard skin on the toe removed. Now I have to go every three weeks. I use padding, but it doesn’t help. — G.C.

ANSWER: Four of the foot’s five toes have three joints. The big toe has only two. The toe next to the big toe is the one that most frequently becomes a hammertoe. The middle joint of that toe becomes permanently bent. The top part of the toe is forced downward into the shoe, and the middle joint juts upward and rubs against the upper part of the shoe. The whole affair looks something like a piano hammer. Calluses and corns develop at spots where the toe rubs against the shoe.

Wearing too small a shoe and high-heel shoes promote hammertoes. Most people, however, have a genetic tendency to develop one.

If the joint isn’t frozen in the bent position, splints or other such devices can slowly unbend it.

Even though you don’t want to hear about surgery, some fairly simple procedures can straighten the toe. You ought to talk to a podiatrist or an orthopedic surgeon.

DEAR DR. DONOHUE: My boyfriend was a heroin addict for more than three years, but he has been drug-free for 15 months. The problem is erectile dysfunction. We have read on the Internet that heroin might be the cause. He is trying several herbs. Will this problem ever go away? Should we make an appointment with a doctor? Would Cialis be the answer? — E.P.

ANSWER: Yes, your friend should see a doctor. By pinning the problem on former heroin use, you could be missing one of the other many causes of erectile dysfunction. Viagra, Levitra and Cialis are possible answers. That’s another reason to see the doctor.

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.