Rectal bleeding

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Rectal bleeding

Finding blood in your stool can be alarming. Prompt diagnosis is essential.

Finding blood in your stool can be alarming. Often, the underlying cause can be treated or controlled. Even if the cause isn't serious, early diagnosis is important.

Causes are varied

Bleeding from your rectum can occur for many reasons, including:

  • Constipation. Passing hard, dry stools may scrape or tear your anal lining, causing an anal fissure. You may notice small drops or streaks of bright red blood on your stool, on your toilet tissue or in the toilet bowl.
  • Hemorrhoids. These swollen and inflamed veins in your anus and rectum are another source of rectal bleeding. Again, you may notice small drops or streaks of bright red blood on your stool, on your toilet tissue or in the toilet bowl.
  • Diverticular bleeding. Diverticula are small, bulging pouches in the large intestine. Diverticula may cause painless, but sometimes severe bleeding.
  • Infection. Some bowel infections cause diarrhea and rectal bleeding. Abdominal cramping, nausea, vomiting and fever may be present as well. These infections are usually caused by eating contaminated food.
  • Colon polyps. A polyp is a small clump of cells. Although most colon polyps are harmless, some may eventually become cancerous. You may notice bright red blood on your toilet tissue after you've had a bowel movement.
  • Peptic ulcers. Peptic ulcers are open sores that develop on the lining of the stomach, upper small intestine or esophagus. Sometimes the ulcers bleed. In addition to upper abdominal pain, you may notice dark blood in your stools or black, tarry stools.
  • Inflammatory bowel disease. Ulcerative colitis and Crohn's disease are examples of inflammatory bowel disease. These often painful and debilitating conditions cause chronic inflammation of the digestive tract. Food moving through your digestive tract can cause the inflamed tissue to bleed. You may notice bright red blood in the toilet bowl or darker blood mixed with your stool.
  • Lack of blood supply to the bowel. If the blood flow to your small intestine or colon is reduced, you may develop intestinal ischemia. This may cause bright red or maroon-colored blood in your stool.
  • Colorectal cancer. Most colon and rectal cancers begin as small, harmless clumps of cells called polyps. Eventually, some of these polyps may become cancerous. You may notice rectal bleeding, along with a change in bowel habits, narrow stools, abdominal discomfort, a feeling that your bowel doesn't empty completely and unexplained weight loss.

In addition, iron supplements, certain foods — such as beets, licorice or blueberries — and some medications — such as bismuth subsalicylate (Pepto-Bismol) — may change the color of your stools to red, maroon or black.

When to see your doctor

Consult your doctor at the first sign of rectal bleeding. Often, the bleeding is temporary and easily treated. Sometimes, however, the bleeding may be a warning sign of something more serious. Prompt diagnosis and treatment could save your life. Treatment depends on what's causing your bleeding.

What are artificial sweeteners?

Artificial sweeteners are chemicals that offer the sweetness of sugar without the calories. Because the substitutes are much sweeter than sugar, it takes a much smaller quantity of them to create the same sweetness. Therefore, products made with artificial sweeteners have a much lower calorie count than do those made with sugar. Artificial sweeteners are often used as part of a weight-loss plan or as a means to control weight gain.

People with diabetes may use artificial sweeteners because they make food taste sweet without raising blood sugar levels. But keep in mind that if you do have diabetes, some foods containing artificial sweeteners, such as sugar-free yogurt, can still affect your blood sugar level due to other carbohydrates or protein in the food. In addition, some foods labeled "sugar-free" — such as sugar-free cookies and chocolates — may contain sweeteners such as sorbitol or mannitol that contain calories and can affect your blood sugar level. Some sugar-free products may also contain flour, which will raise blood sugar levels.

Safety of artificial sweeteners

Artificial sweeteners are often the subject of stories in the popular press and on the Internet, claiming that they cause a variety of health problems, including cancer. According to the National Cancer Institute, however, there's no scientific evidence that any of the artificial sweeteners approved for use in the United States cause cancer. And numerous studies confirm that artificial sweeteners are safe for the general population.

Aspartame does carry a cautionary note, however. It isn't safe for people who have the rare hereditary disease phenylketonuria (PKU). Products that contain aspartame must carry a PKU warning on the label.

Last Updated: 04/27/2007
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