Red stool is usually caused by something you ate or drank in the last day or two, not by bleeding. Beets, red gelatin, red-dyed snack foods, fruit punch, and red licorice can all turn your stool visibly red. That said, actual bleeding in the digestive tract can also produce red stool, so it’s worth knowing how to tell the difference.
Foods and Drinks That Turn Stool Red
Beets are the most common culprit. They contain a pigment called betanin that some people can’t fully break down during digestion. The undigested pigment passes through and stains both stool and urine a startling shade of red or pink. This is completely harmless and typically clears within 48 hours of your last serving.
Other common causes include red-colored gelatin (like Jell-O), Kool-Aid or fruit punch, red licorice, and spicy red-dyed snack foods like Flamin’ Hot Cheetos. Tomato soup, tomato sauce, and cranberry juice can also produce a reddish tint. If you ate any of these in the past day or two, that’s very likely your answer. If the color persists more than 48 hours after you stop eating the suspect food, something else is going on.
Medications That Can Cause It
Certain antibiotics can make stool appear red, though in some cases antibiotics cause actual intestinal bleeding rather than just a color change. If you recently started an antibiotic and notice red stool, it’s worth mentioning to your prescriber. Red-colored liquid medications, supplements with red dye, and bismuth-containing products (like Pepto-Bismol) can also change stool color, though bismuth typically turns it black rather than red.
Hemorrhoids and Anal Fissures
If you’re seeing bright red blood on the toilet paper, on the surface of your stool, or dripping into the bowl, the two most common causes are hemorrhoids and anal fissures. Both involve the very end of the digestive tract, which is why the blood looks bright red rather than dark.
Hemorrhoids tend to cause an achy or itchy discomfort that comes and goes. Bleeding can be noticeable, sometimes with larger clots, and you might feel a soft lump near your anus. Anal fissures, which are small tears in the lining of the anus, produce a sharp, burning pain that can last for hours after a bowel movement. The bleeding from a fissure is usually a smaller amount of bright red blood on the toilet paper. Both conditions are more likely if you’ve been constipated, straining, or passing hard stools.
What the Color of Blood Tells You
The shade of red matters because it signals where in your digestive tract the bleeding is coming from. Bright red or maroon blood generally means the source is lower, in the colon, rectum, or anus. Black, tarry stool means blood has been digested on its way through, pointing to bleeding higher up in the esophagus, stomach, or small intestine.
There’s an important exception: maroon or red stool can sometimes come from an upper source like a stomach ulcer if the bleeding is heavy enough that blood moves through the system quickly without turning black. That scenario involves large volumes of blood and is a medical emergency.
Inflammatory Bowel Disease
Bloody stool is one of the hallmark symptoms of ulcerative colitis, a condition where the lining of the colon becomes chronically inflamed. Early signs include diarrhea (with or without blood), urgent need to use the bathroom, mild abdominal cramping, and the frustrating sensation of needing to go but being unable to. As the condition progresses, you might notice blood, mucus, or pus in your stool along with more frequent diarrhea, four or more episodes a day.
Ulcerative colitis also causes symptoms beyond the gut in about 25% of people, including joint pain and swelling, red or burning eyes, and skin rashes or ulcers. If bloody stool is accompanied by ongoing diarrhea, cramping, unexplained weight loss, or any of these other symptoms, that pattern points toward something more than a simple hemorrhoid.
Signs You Need Immediate Help
Most causes of red stool are either harmless (food dye) or manageable (hemorrhoids). But certain warning signs indicate significant blood loss that needs emergency care. These include feeling lightheaded or dizzy when you stand up, a racing heartbeat, cold or clammy skin, confusion, or passing large amounts of blood. Fainting or feeling like you might faint is a clear signal to get to an emergency room. These symptoms suggest your body is losing blood faster than it can compensate.
Passing a large volume of maroon or bright red blood, even without those other symptoms, also warrants urgent evaluation.
How Red Stool Gets Evaluated
If you see a provider about rectal bleeding, the workup typically starts simple and gets more involved only if needed. A physical exam of the rectal area can identify hemorrhoids or fissures on the spot. From there, your provider may recommend a closer look with a scope that examines just the anus and lower rectum, or a flexible sigmoidoscopy that reaches further into the lower colon.
A fecal occult blood test checks for hidden blood that isn’t visible to the naked eye. If there’s concern about a source higher in the colon or elsewhere in the digestive tract, a full colonoscopy examines the entire colon, while an upper endoscopy looks at the stomach and small intestine. The sequence depends on your age, symptoms, and how much bleeding you’ve had.
For average-risk adults, routine colorectal cancer screening is now recommended starting at age 45. If you’re 45 or older and haven’t been screened, red stool is a reasonable prompt to get that process started, even if the cause turns out to be something benign.