DEAR DR. DONOHUE My son is 36, and his doctor has told him he has too much iron in his blood. They removed blood from him. After it was removed, he felt tired and weak. His doctor said he has hemochromatosis. What is this? Is it serious? – Anon.

ANSWER: Hemochromatosis (HE-moe-CROW-muh-TOE-suss) is a word that doesn’t strike a familiar chord in most people’s brains. That’s unfortunate, for it is the most common inherited disease in people whose ancestors came from Northern Europe. About one in 300 whites has the disease, a sizable number of people. A person with only one hemochromatosis gene is a carrier and has no symptoms. It takes two genes, one from the father and one from the mother, for a person to have the actual illness.

In normal people, the digestive tract lets only the needed amount of iron pass from the tract into the blood. In people with hemochromatosis, the digestive tract permits the absorption of too much iron. The excess iron makes its way to the liver, the pancreas, the skin, joints, eyes and sex organs. By the time a man with hemochromatosis reaches 40 or 50, destruction of those organs begins to show. Women do not have symptoms until 10 years later. Menstruation helps them lose iron while they still have menstrual cycles.

The liver is the prime target. It becomes scarred and cannot function. A pancreas filled with iron cannot produce insulin, so diabetes is a common consequence. In skin, iron deposits create a bronzed appearance. Joints can suffer a special kind of arthritis. An iron-loaded heart cannot pump normally. Iron in the testicles causes them to shrink.

All can be avoided by early detection. Removing blood is the treatment. Blood is the body’s major depository of iron. Your son will feel much better in time. Blood removal continues for life.

All close relatives need to be screened.

Canadian and American hemochromatosis patients have two wonderful friends who can supply them with the latest information on treatment. People can reach the Canadian Hemochromatosis Society by phone, by Internet or by letter at: 1-877-223-4766; www.cdnhemochromatosis.ca; 272-7000 Minoru Blvd., Richmond, BC, Canada, V6Y 3Z5. People can contact the American Hemochromatosis Research Foundation at www.hemochromatosis.org or Box 8569, Albany, NY 12208.

DEAR DR. DONOHUE: I completed a series of radiation treatments to my prostate gland. The doctor was pleased with the results. Now I have a mucus discharge from the rectum, and sometimes the discharge is pink or red. I take this to be blood. What can I do? – B.R.

ANSWER: The rectum is the prostate gland’s next-door neighbor. Radiation to the gland can strike the rectum and irritate it. The irritation often disappears on its own. If the symptoms are bothersome, try soaking daily in a tub of warm water. Azulfidine, a medicine used for ulcerative colitis, can sometimes bring relief. Cortisone enemas are another possible treatment.

You must tell your doctor that you are having this trouble.

DEAR DR. DONOHUE: For the past seven years I have had hives and itching in any area exposed to cold for too long. I can’t turn the air conditioning vent in my car toward my neck or it starts itching. Is there a name for this? – K.M.

ANSWER: The name of the condition is cold urticaria. “Urticaria” is the medical word for hives. Cold urticaria is unusual. It is not triggered by an allergen such as pollen. It is triggered by a natural, material force – cold. Pressure urticaria, vibration urticaria and heat urticaria are examples of other types of urticaria in which physical forces can precipitate an attack of hives.

I don’t mean to be insulting, but the obvious solution is to avoid cold. If you know you are going to deal with a cold environment, taking an antihistamine in advance might prevent an attack. Nonsedating antihistamines such as Zyrtec and Allegra are two good choices.

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.