DEAR DR. DONOHUE: My 8-year-old son is in the third grade. School has been a problem for him from the start. He’s a very active little boy and finds it hard to sit still, even at home. Teachers have suggested he has attention-deficit hyperactivity disorder and urge us to put him on Ritalin. My husband is opposed to it, and I don’t know. We would like to hear what you have to say. – R.T.

ANSWER: There is no single test that identifies a child (or an adult) as having attention-deficit hyperactivity disorder – ADHD. There is, however, a list of signs and symptoms that define it, and a child with many of those signs and symptoms can reliably be said to have it.

Among the criteria are a failure to pay attention to details; constant repetition of careless mistakes; an inability to stay focused; not listening when spoken to; a failure to finish schoolwork or home tasks; distractibility; constantly losing books, pencils or other tools; forever leaving the school seat; blurting out answers; and nonstop fidgeting. Admittedly, many of those characteristics are characteristics of the average 8-year-old, but most children of that age do not have all or most of the listed ADHD traits.

Medicines are one approach to treatment. Medicating a young child should make everyone pause. If the parents agree the child has ADHD, if the family doctor or pediatrician concurs, if teachers believe it and if an expert in this field feels that it is the case, then a trial of medicine might be in the child’s best interests. ADHD treatment should follow medicine’s prime maxim: Above all, do no harm.

Don’t forsake other ways of dealing with the problem. There are programs that teach parents how to reward the good behavior and ignore the bad behavior of an ADHD child and help the youngster to alter disruptive impulsiveness. Your family doctor or the school social worker can put you in touch with facilities that sponsor such programs.

DEAR DR. DONOHUE: Last week my urine turned a dark, reddish-brown color. I guess it had blood in it. I had no pain at the time or since, and it has not happened again. What should I do about it? I can’t see a doctor right now, as I have no insurance and no job. – W.N.

ANSWER: Blood can give urine a red, pink or brown color, so what you saw might represent bleeding in the urinary tract. Other things can impart similar colors. Food colorings, some medicines, beets, and the breakdown of red blood cells or muscle cells can match the color you saw.

Pain along with such a color change points to things like kidney stones or infections of the kidney or bladder.

Such color change without pain can result from vigorous exercise, inherited kidney conditions and a variety of kidney inflammatory illnesses.

The most dangerous condition, of course, is cancer, and it can cause either painless or painful bleeding.

Even though this happened only once, and even though you are strapped for money and have no insurance, you really do need medical attention to ferret out all the possibilities. Have you tried calling a doctor and explaining your circumstances and asking that costs be deferred until you are back on your feet? This is an issue that demands an immediate answer.

DEAR DR. DONOHUE: What’s the meaning of “fungus on the lungs”? The nurse from my doctor’s office called to give me the report of a chest X-ray. That’s what she said I had. She said I didn’t need any treatment. When I pressed for details, she couldn’t give them to me. Can you? – P.R.

ANSWER: Lots of fungi infect the lungs. I’m sticking my neck out, but the nurse might have been speaking of histoplasmosis, a common fungal infection in the Midwest and Ohio Valley. Most of the time, people never know they have been infected with this fungus. It often produces no symptoms. X-ray changes, however, are quite dramatic. The fungus is no longer living. Only its remains are seen on the X-ray, and usually no treatment is called for. Please, confirm this guess, which is all that this is.

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.