Seeing blood when you poop is alarming, but in most cases the cause is something minor and treatable. Hemorrhoids are the single most common reason for blood in stool. That said, rectal bleeding can also signal something more serious, so knowing how to read the signs and when to act matters.
What the Color of the Blood Tells You
The color and appearance of the blood is the most useful clue about where the bleeding is coming from. Bright red blood typically originates low in the digestive tract, usually the rectum or anus. This is the kind you notice on toilet paper, dripping into the bowl, or coating the surface of your stool. It often points to hemorrhoids or a small tear in the anal lining.
Dark red or maroon blood tends to come from higher up in the colon, which can indicate problems like infected pouches in the colon wall (diverticulitis) or inflammatory bowel disease.
Black, tarry, sticky stools are a different category entirely. Blood that starts in the stomach or upper intestines gets broken down by digestive enzymes on its way through the gut, turning it dark. Black tarry stools suggest bleeding well above the colon and generally need prompt medical attention.
The Most Common Causes
Hemorrhoids, which are swollen veins in the rectum or anus, cause the majority of rectal bleeding in adults. They typically develop from straining during bowel movements, sitting for long periods, or chronic constipation. The bleeding is usually painless and bright red.
Anal fissures are the second most common culprit. These are small tears in the lining of the anal canal, usually caused by passing hard or large stools. Unlike hemorrhoids, fissures tend to cause sharp pain during and after a bowel movement along with the bleeding.
Less common but more serious causes include:
- Diverticulitis: Small pouches that form in the colon wall can become infected and inflamed, making the blood vessels inside fragile enough to rupture.
- Inflammatory bowel disease (IBD): Conditions like ulcerative colitis and Crohn’s disease cause chronic inflammation in the intestinal lining, which can lead to bleeding, diarrhea, and abdominal pain.
- Colorectal polyps or cancer: Growths in the colon or rectum can bleed, sometimes without any other symptoms.
When to Go to the ER
Most rectal bleeding does not require an emergency room visit. But certain combinations of symptoms mean something more urgent is happening. Get emergency care if you notice a large volume of blood (not just streaks or drops), especially if it’s dark red or maroon. Lightheadedness, dizziness, a rapid heartbeat, or feeling like you might faint alongside bleeding suggests you’re losing enough blood to affect circulation. Severe abdominal pain with bleeding also warrants immediate attention.
If you’re bleeding and take blood-thinning medications, err on the side of getting checked sooner rather than later, since even minor sources of bleeding can become harder for your body to control.
What You Can Do at Home
If the bleeding is small in volume, bright red, and seems related to straining or hard stools, it’s reasonable to try managing it at home for a few days while you monitor things.
Warm sitz baths are one of the most effective immediate remedies for hemorrhoid and fissure discomfort. Sit in a few inches of warm water for about 15 minutes, several times a day, and especially after bowel movements. This reduces swelling and helps the area heal.
Softening your stools is the other priority. Increase your fiber intake gradually with fruits, vegetables, whole grains, or a fiber supplement like psyllium husk. The key word is gradually. Adding too much fiber at once can cause gas and cramping, which makes things worse. Drink plenty of water alongside the extra fiber, since fiber without adequate hydration can actually harden stools. Avoid straining on the toilet. If you have to push hard, get up, walk around, and try again later.
Over-the-counter creams and suppositories designed for hemorrhoids can relieve itching and discomfort in the short term. These won’t fix the underlying problem, but they make the healing period more comfortable.
When to Schedule a Doctor Visit
Even if the bleeding seems minor, schedule an appointment if it continues for more than a week, keeps coming back, or is accompanied by changes in your bowel habits like persistent diarrhea, narrower stools, or unexplained weight loss. Abdominal pain or cramping alongside rectal bleeding also deserves a closer look.
Before your appointment, take note of a few things your doctor will want to know: how often the bleeding happens, what color it is, whether it’s mixed into the stool or separate, whether you have pain, and whether anything else has changed with your digestion. These details help narrow down the cause quickly.
What Happens at the Doctor’s Office
Your doctor will start with your medical history and a physical exam, which typically includes a visual and manual check of the anal area. For many cases of bright red bleeding in younger patients, this is enough to identify hemorrhoids or a fissure.
If the cause isn’t obvious, or if your symptoms suggest something beyond the rectum, the next step is usually a scope. A flexible sigmoidoscopy uses a small camera to examine the rectum and lower colon. A colonoscopy covers the entire large intestine and is the most thorough way to check for polyps, inflammation, or other problems. During a colonoscopy, the doctor can also remove polyps or take tissue samples on the spot.
The U.S. Preventive Services Task Force recommends that all adults begin routine colorectal cancer screening at age 45, continuing through age 75. If you’re in that age range and haven’t been screened, rectal bleeding is a good reason to stop putting it off. If you’re under 45 with persistent or unexplained bleeding, your doctor may still recommend a colonoscopy based on your symptoms.
Bleeding That Comes and Goes
One pattern that trips people up is intermittent bleeding. You see blood for a day or two, it stops, and you figure the problem resolved itself. Weeks or months later it returns. Hemorrhoids and fissures do behave this way, flaring and calming based on your diet and bowel habits. But so can polyps and early-stage colorectal cancers. The on-and-off pattern alone doesn’t tell you the cause, so recurring episodes are worth getting evaluated even if each individual episode seems small.
A few foods and supplements can also change the color of your stool and mimic bleeding. Beets, red gelatin, and iron supplements can make stools appear red or black. If you recently ate something that could explain the color and you have no other symptoms, that may be all it is. But if you’re unsure, it’s always safer to treat it as real blood until proven otherwise.