Question:

Is blood in your poop cause for concern?

Answer from Nebraska Medicine gastroenterologist Jalpa Devi, MD, MBBS:

“Seeing blood in your stool can be scary—but it doesn’t always mean something serious is going on,” says Dr. Devi. “The cause depends on several factors, including how much blood you see, the color of the blood, how often it happens and whether you have other symptoms.”

What does the color of blood mean?

The color of the blood can give clues about where it’s coming from:

• Bright red blood usually comes from the lower digestive tract, such as the rectum or anus.

• Dark maroon or black, tarry stools may mean the blood is coming from higher up, like the stomach or small intestine. This can be more serious and often needs urgent care.

Common causes of blood in stool

Bright red blood
The most common causes are usually not serious:

• Hemorrhoids: Swollen veins in the rectum or anus. They often cause small amounts of bright red blood, especially with constipation or straining.

• Anal fissures: Small tears in the skin around the anus that can cause pain and bleeding during bowel movements.

Other possible causes include:

• Infections that cause diarrhea.

• Inflammatory bowel disease (IBD), such as Crohn’s disease or ulcerative colitis—especially if blood is paired with diarrhea, mucus, abdominal pain or a family history of autoimmune disease.

• Blood thinners (anticoagulants and antiplatelet medications), which can make bleeding more noticeable.

• Colon polyps or colorectal cancer, adults 45 or older should be regularly screened for colon cancer even with no symptoms. If you have a family history of colorectal cancer and notice blood in your stool, see a doctor immediately for further evaluation.  

Dark or black stools
Dark, sticky, black stools can mean bleeding in the upper digestive tract. Possible causes include:

• Stomach ulcers, often linked to frequent use of NSAIDs (like ibuprofen).

• Alcohol-related liver disease, which can lead to bleeding in the esophagus.

• Other conditions affecting the stomach or small intestine.

These symptoms need more urgent evaluation.

Certain medications, such as iron supplements or bismuth-containing products, may also darken stool without indicating bleeding. 

When should you be concerned?

You should seek immediate medical care or go to the emergency room if you have:

• A large amount of blood.

• Blood clots.

• Black, tarry stools.

• Dizziness, weakness or fainting.

• Bloody stool with severe diarrhea.

You should schedule a doctor’s visit if you notice:

• Ongoing or repeated bleeding.

• Blood mixed throughout the stool.

• A change in bowel habits (new diarrhea or constipation).

• Unexplained weight loss, fatigue or abdominal pain.

“If bleeding is mild and happens only occasionally—such as small streaks on toilet paper with constipation—start by talking with your primary care provider,” says Dr. Devi. “Even mild symptoms should still be checked to make sure nothing more serious is going on.”

How doctors find the cause

Diagnosis depends on your symptoms:

• Mild bleeding with constipation: Your provider may do a rectal exam and recommend treatment for constipation or hemorrhoids.

• Pain with bowel movements: This may point to an anal fissure.

• Bleeding with diarrhea, fatigue or family history of IBD: Further testing may include blood work, stool tests, imaging or a colonoscopy.

• Dark or black stools: An upper endoscopy may be needed, and urgent evaluation is often required.

• Heavy or ongoing bleeding: This requires prompt medical attention, often in the emergency room.

How blood in stool is treated

Treatment depends on the cause:

• Hemorrhoids and anal fissures: Treatment focuses on relieving constipation and reducing strain. Doctors may also prescribe medications or topical treatments. 

• Infections: Treated based on the cause.

• Inflammatory bowel disease: Managed with medications tailored to the type and severity of disease.

• Stomach ulcers: Often treated by stopping NSAIDs and treating infections like H. pylori if present.

• Alcohol-related causes: Treatment focuses on managing liver health and preventing further bleeding.

• Polyps or cancer: Managed with specialized care and follow-up.

It’s important not to self-diagnose or treat bleeding without seeing a healthcare provider.

Final thoughts: Don’t ignore blood in your stool

Even if bleeding is mild, happens only once in a while or stops on its own, it shouldn’t be ignored. Seeing a doctor helps rule out serious conditions and ensures you get the right treatment early.