Blood in Stool (Hematochezia): Causes, Colors, Tests, and Treatment 

Key takeaways:

• Hematochezia means having blood in your stool. It can be caused by minor issues like anal fissures (cracks or tears in the tissues that line the anal canal) or more serious conditions like cancer.
• Blood in stool can look black, tarry-like, or bright red. Also, it can occur with or without pain.
• A dark or red-colored stool indicates upper or lower gastrointestinal tract bleeding. Your food can also change the color of your stool.
• Hematochezia can be accompanied by symptoms such as rectal pain, abdominal pain, and vomiting. 

It may be distressing to notice that your stool has blood or that there is blood on your toilet paper after wiping. While this is not an automatic cause for alarm, it can indicate an underlying medical issue.

In this article, you’ll learn about the causes of blood in stool, the symptoms that can accompany a bloody stool, and when to see a doctor. But first, let’s answer an important question.

Is rectal bleeding the same as hematochezia?

Rectal bleeding and hematochezia mean the same thing. Hematochezia is the medical term for rectal bleeding, which is the passage of blood in the stool.

Causes of blood in stool

Blood is found in stool for several reasons, and they include the following:

1. Inflammatory Bowel Disease (IBD)

Crohn's disease and ulcerative colitis, known as inflammatory bowel diseases (IBD), cause chronic inflammation of the gastrointestinal tract, which can lead to blood being present in the stool.

There is no known cause of IBD, but experts are of the opinion that changes to the immune system and genetic factors play a role.

2. Hemorrhoids

Hemorrhoids, also called piles, are swollen veins in and around the lower rectum and anus that can cause pain and bleeding. Pregnancy, obesity, heavy lifting, and straining while passing stool are common risk factors for developing hemorrhoids.

3. Anal fissure

Anal fissures are small tears and sores on the lining of the anus. They cause pain and bleeding during and after bowel movements. Anal fissures can affect anyone, but they’re more common in infants and middle-aged people.

4. Colon polyps

Colon polyps are small clumps of cells that appear on the lining of the large intestine or rectum. Sometimes, polyps bleed and cause hematochezia. Most are harmless, but some can develop into colon cancer.

5. Colorectal cancer

Colorectal cancer usually develops from polyps. Cancerous growths can weaken the gastrointestinal tract lining and lead to bleeding in the later stages of the cancer.

6. Diverticular disease

Diverticulosis is a condition in which small, bulging pouches develop in the digestive tract. These pouches are prone to bleeding and infection. Diverticulitis occurs when these pouches become infected or inflamed.

Diverticulosis is common in those over 40, and 10 to 25 percent of people with diverticulosis develop diverticulitis.

7. Peptic ulcer

Peptic ulcers are open sores in the stomach lining or the duodenum (upper end of the small intestine). A peptic ulcer can cause serious complications like internal bleeding, and bloody stools. 

The most common causes of peptic ulcers are infection with a bacterium called Helicobacter pylori (H.pylori) and prolonged use of nonsteroidal anti-inflammatory drugs (NSAIDs).

8. Medication

Gastrointestinal bleeding is a common side effect of blood-thinning medications such as Warfarin and Enoxaparin. Notify your doctor immediately if you’re on a blood-thinning medication and experience hematochezia.

The different colors of stool with blood and what they indicate

The color of bloody stools varies depending on which part of the gastrointestinal tract is bleeding.

Black stool

A black stool suggests that the bleeding is happening in the upper gastrointestinal tract. The upper gastrointestinal tract includes the mouth, esophagus, stomach, and duodenum. 

Bright, red stool

A stool with the color of fresh blood is a sign of a bleed in the lower gastrointestinal tract, which consists of the small and large intestines, rectum, and anus.

Other symptoms that can accompany blood in stool

The symptoms of hematochezia depend on the location, cause, and severity of the bleeding. They may include:

• Rectal pain 
• Abdominal pain 
• Nausea 
• Vomiting
• Constipation  
• Diarrhea 
• Weakness 
• Weight loss 
• Anemia 

Diagnosis

Your doctor will ask questions about your symptoms to help locate the bleeding site. Based on your answers, they may carry out a rectal exam and order tests to identify the cause of the bleeding.

Your doctor may recommend any of these tests or procedures:

• Upper GI endoscopy: Involves inserting an endoscope, an inspection instrument equipped with a light and camera, down the upper gastrointestinal tract.
• Colonoscopy: A colonoscopy is also performed with an endoscope. However, the endoscope is inserted into the body via the anus to view the colon and rectum.
• Barium swallow: Is an imaging test that uses barium and X-rays to examine your upper gastrointestinal tract. You’ll drink a mixture of barium and water before taking the X-rays. The barium outlines the walls of your upper gastrointestinal tract and reveals details that can’t be seen on a standard X-ray image.
• Blood tests: These tests check if your immune system works properly, help determine the amount of blood lost through hematochezia, and assess your risk of excessive bleeding.
• Laparotomy: This is a surgical procedure in which the surgeon opens up and examines the abdominal cavity. This approach may become necessary if other tests fail to detect the source of the bleeding.

Treatment

The treatment option your doctor will suggest depends on what is causing the hematochezia.

For example, if you have an anal fissure or hemorrhoids, your doctor may instruct you to increase your fiber intake and drink more water. These remedies soften your stool and relieve constipation so that you can heal.

If the cause of the rectal bleeding is an ulcer or a medical condition like IBD, your doctor will prescribe the necessary medication. A diet modification may also be recommended.

Surgery is usually required for polyps and colorectal cancer to remove the offending growth. In some cases, parts of the colon damaged by cancer will have to be removed through a procedure known as colectomy.

When to see a doctor

A bright red or dark stool does not necessarily mean there is bleeding in your gastrointestinal tract. Certain medications and foods can change the color of your stool.

Iron supplements, black licorice, blueberries, and blood sausage can make your stool black, while beets and foods with red coloring can make your stool appear reddish.

If the color of your bowel movements changes for some time and then quickly returns to normal, it’s likely due to something you ate.

Contact your healthcare provider if you consistently notice blood in your stool or on tissue paper. You should also check in with your doctor if there’s a prolonged change in the color of your stool.

Seek immediate medical attention if severe symptoms like fever and vomiting accompany hematochezia or if the bleeding is heavy and continuous.