ANSWER: The colon is about 5 feet long. It begins in the lower-right side of the abdomen, ascends on the right to just below the liver, crosses over the abdomen to the left side and then descends to the rectum.

Symptoms of colon cancer depend where the cancer is located. Cancers on the right side often cause open sores that bleed. Since it takes a while for undigested food to reach the rectum from the right side of the colon, the blood often is seen as tarry, black stool. Cancers of the section of colon that spans the upper part of the abdomen from the right to the left sides can cause obstruction of the bowel. Cancers of the left side of the colon, the most common site for colon cancer, can lead to narrow stools, cause stomach cramps and discharge bright-red blood into the stool. Weight loss is a sign of colon cancer, regardless of its site.

Don’t wait for symptoms to check for colon cancer. This cancer has a number of excellent screening tests, and it can be detected early, when it’s treatable and curable. Everyone at age 50 should have a colonoscopic exam, a scope exam of the colon. The examining doctor sees every inch of the colon and spots any cancer or any polyps, the precursors of colon cancer. X-rays called double-contrast barium enemas are another way of detecting colon cancer.

The booklet on colon cancer deals with its detection and treatment. Readers can order a copy by writing: Dr. Donohue – No. 505, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.75 U.S./$6 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

DEAR DR. DONOHUE: For about five months I have had numbness on the left side of my face, cheek, nose, lips and chin. The neurologist and my primary care physician, after X-rays and blood tests, decided I have a deficiency of vitamin B-12. (My blood tests are enclosed.)

Now I am popping large doses of B-12 daily. I didn’t want to take the shots. So far, there has been no improvement. Is there a research facility near me where I could have the diagnosis verified? – J.A.

ANSWER: Vitamin B-12 deficiency can produce nerve damage. Your blood tests do point to a low level of that vitamin. Restoration of nerve function takes a long time. The anemia that is caused by B-12 lack clears much more rapidly. Perhaps it’s only a matter of time before you see a difference.

You live on the West Coast near a city that has two outstanding medical schools. If you want a second opinion, call the neurology department of either of those schools for an appointment.

DEAR DR. DONOHUE: I am a 67-year-old dentist who had a health-related problem that may be educational for your readers. I had extensive back surgery and because of the pain, I became addicted to Lortab (hydrocodone), a narcotic. I went to rehabilitation for this addiction.

Before rehab, my ankles were swelling. I went through several heart tests but nothing showed abnormal. On entering rehab, an older physician did a complete exam. I asked him about the swelling, and he stated that some individuals addicted to this medicine developed swelling like mine.

After six days of rehab, I lost eight pounds, and the swelling disappeared and has not returned. – J.P.

ANSWER: Thanks, doctor, for your interesting and frank story. Long-term opioid use (drugs related to morphine, opium) can cause swelling due to leakage of fluid from capillaries. The leakage comes from histamine release secondary to those drugs.

DEAR DR. DONOHUE: What causes bags under the eyes? – L.B.

ANSWER: In younger years, tough fiber strands under the eyes form a grill that keeps fat from bulging forward. In older years, those strands give way and fat protrudes to make undereye bulges – bags.

DEAR DR. DONOHUE: My wife has cryptogenic organizing pneumonia. What is this disorder? What causes it? Does it recur? – L.V.

Cryptogenic organizing pneumonia causes a flulike illness with a dry cough and breathlessness. “Pneumonia” means lung inflammation. “Organizing” indicates that strands of scarlike tissue have developed in the inflamed tissues. The cause of this illness remains hidden (“cryptogenic”).

The majority of patients completely recover with the use of steroids – usually prednisone, one of the cortisone drugs and one of the best inflammation suppressants available. It can take six months to feel like oneself again.

Formerly, cryptogenic organizing pneumonia was called BOOP, bronchiolitis obliterans with organizing pneumonia.

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

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