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Bright Red Blood in Stool: When Should You See a Doctor?


Blood in the stool isn’t always visible to the naked eye, but it can be alarming when it is. It can range from dark and tarry to a coffee ground consistency to bright red. Many people won’t recognize dark, tarry stool as containing blood, but very few mistake bright red blood in the toilet bowl for anything else.

Did you know that the color hints at which part of your digestive tract is bleeding? The darker the blood, the longer it’s had to travel through your digestive tract.

Dark, tarry-looking stool generally contains blood from the stomach, such as a bleeding ulcer.

Maroon or dark blood typically means the bleeding originates higher up in the colon or the small bowel. And if it’s bright red, it is from the end of your digestive tract and hasn’t traveled far.

Is bright red blood in stool serious? Most of the time, it’s not. But there are times when it could be a serious health condition. Read more to learn about when you should see a doctor.

What causes blood in stool?

Seeing blood in the toilet bowl can be scary. You may have heard that blood in the stool can mean cancer – but it usually doesn’t. Blood in the stool can have a number of causes ranging from serious to easily treated. And the most common cause is also one of the less serious.

What does bright red blood in stool mean?

Bright red blood is from your colon or rectum – near the end of your digestive tract. The colon has a lot of blood vessels, which means an injury to the colon can cause bright red rectal bleeding. Common causes of bright red blood in the stool include:


Hemorrhoids are the most common cause of bleeding with a bowel movement. They are swollen veins in or around the anus that may bleed if you scratch them or if one develops a blood clot.

You’ll most often notice the blood when wiping. Many people don’t even realize they have hemorrhoids until one bleeds. The symptoms of hemorrhoids tend to come and go and can usually be treated successfully at home.

Anal fissures

Anal fissure is a medical term for a small tear in the anus, like a paper cut. A tear can be caused by pushing to have a bowel movement, large stools, frequent diarrhea, or otherwise putting strain on the anus. They can be uncomfortable and itchy but generally, heal at home.

Soaking in warm water can help the healing and discomfort. Like hemorrhoids, you’ll most often notice the blood from anal fissures when wiping.

Infection in the bowel

Bacterial or parasitic infections can cause bloody diarrhea. Bacterial infections are most often foodborne, like Salmonella or E. coli. Infections may also cause abdominal pain, fever, nausea, and vomiting. Antibiotics may be needed to clear up an infection in the bowel.

Inflammation in the bowel

Certain bowel conditions can cause inflammation or sores, leading to bleeding in the colon. Diverticular disease and inflammatory bowel disease (IBD), which include Crohn’s disease and ulcerative colitis, can all cause bleeding.

Polyps or cancer in the colon

Polyps are growths in the large intestine that can turn into cancer over time. They don’t often cause symptoms, and most people don’t realize they have polyps. When they do cause symptoms, they often include red blood in the stool or rectal bleeding. Bleeding caused by cancer tends to continue or get worse over time. The only way to know if you have polyps is to have a colonoscopy.

When to worry about blood in stool

Sometimes you can pinpoint the cause of blood in your stool. For example, if you have a history of hemorrhoids or had a recent bout of diarrhea or constipation that put unusual strain on the anus. In those cases, treating the underlying problem tends to resolve the bleeding – and warm soaks help too.

But if you don’t know the cause of the bleeding, or it keeps coming back, it’s a good idea to call your healthcare provider. Infections, inflammatory conditions, and polyps need to be treated by a doctor.

Always call your healthcare provider if:

  • The bleeding doesn’t stop
  • You see large amounts of blood
  • You have other symptoms like pain or pressure in your rectum
  • You feel dizzy, lightheaded, weak, or confused

Nobody expects to see bright red blood with a bowel movement – it can be quite a shock, especially if you can’t think of an obvious cause.

If you do see blood, chances are very good that it was caused by something minor and easily treated. But knowing is best. Call your healthcare provider so you can be sure of your diagnosis and treatment. When rectal bleeding is a sign of something more serious, starting treatment sooner is always better than later.

Don’t continue experiencing blood in stool – schedule an appointment today!


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