For most people, talking about poop is uncomfortable, but if you live with ulcerative colitis (UC), a form of inflammatory bowel disease (IBD), it’s unavoidable — and it’s a crucial part of disease management. Stool changes are one of the clearest, earliest signals of what’s happening inside your gut, and paying attention to any red flags can help you catch a flare before it spirals out of control.
During a UC flare you may encounter changes in your bowel movements, such as going more often, seeing blood or mucus in your stool, or feeling a sudden urgency that’s hard to ignore. For many people living with UC, these changes in bowel movements are the first sign that inflammation is returning after a period of remission.
To understand how UC affects stool, it helps to know what’s considered “normal.” In people without UC, bowel movements happen anywhere from three times a week to three times a day. Stools are typically well-formed, sausage-shaped, and easy to pass, and are a 3 or 4 on the Bristol Stool Chart, a visual medical tool used to classify stool consistency.
In UC, however, your “normal” during remission probably looks different: Perhaps it’s a lack of urgency and rectal bleeding, along with a frequency that’s average for you. If your bowel health is taking a turn from your norm, it’s important to flag changes to your health team — if they do indicate a flare, you’ll need to adjust treatment.
What UC Stool Looks Like During a Flare
Monitoring bowel health and your stools is important for everyone, but even more so for people with ulcerative colitis, says Alan Moss, MD, the chief scientific officer at the Crohn’s & Colitis Foundation and a professor of gastroenterology at Boston University’s Chobanian & Avedisian School of Medicine.
“For people living with UC, paying close attention to stool patterns — frequency, consistency, blood, urgency, and nighttime symptoms — and sharing those details early with your gastroenterology team is one of the most powerful ways to stay ahead of flares,” Dr. Moss says.
If you encounter any of the changes below, tell your IBD team. “No amount of visible blood, persistent diarrhea, or significant change from your ‘usual’ is too minor to mention,” he says.
Consistency
One of the most common signs of a UC flare is diarrhea or loose stools, Moss says. Instead of being formed, stool may be mushy or completely liquid, often falling into Bristol Stool Chart types 5 to 7, he says.
“During a UC flare, bowel movements are usually loose or watery and occur with more urgency than usual,” he says, noting that this may happen multiple times a day rather than as a one-off episode. Stomach cramping often comes along with these stool changes, which are a “strong signal” to call your GI team.
Blood
Fresh blood in the stool, or hematochezia, is a symptom of active ulcerative colitis you shouldn’t brush under the rug, says Supriya Rao, MD, a gastroenterologist and a spokesperson for the American Gastroenterological Association based in Lowell, Massachusetts, where she treats people with IBD or other digestive health issues.
“There is no amount of blood that is considered normal in UC, even if it’s just on toilet paper,” Dr. Rao says. She notes:
Bright red blood usually points to active inflammation in the rectum or lower colon, while darker blood (from higher up) can suggest more extensive disease.
Blood may be mixed throughout the stool, coating it, or appear only on toilet paper after wiping. Either way, even small amounts can signal active disease and should be discussed with your doctor, especially if it’s persistent or increasing.
Heavier bleeding, clots, or darker maroon stool can signal more extensive bleeding and warrants urgent medical attention, Moss says.
Mucus and Pus
The colon produces mucus to protect its lining, but when it’s inflamed, it can produce too much. In people with UC, this excess mucus may appear as clear, white, or yellowish jellylike strands in the toilet or on the stool.
Seeing yellow or green mucus or pus in your stool can also point to infection, Rao says.
Tenesmus
Tenesmus is the painful sensation that you need to go to the bathroom — even though you can’t go or there’s little or nothing to pass. As many as 30 percent of people with IBD experience tenesmus, and it’s a warning sign of chronic inflammation in the lower bowel.
“Tenesmus usually means the disease is no longer fully controlled,” Rao says.
Other Red Flags to Watch For
According to Moss, other important warning signs include:
Rising urgency or a sudden overwhelming need to find a bathroom
Nocturnal bowel movements or waking up at night to poop
Odor changes, including foul-smelling stools, which can indicate malabsorption or an infection, such as from the bacteria Clostridioides difficile
Abdominal pain or sudden cramping
Rectal pain
Fatigue and fever (even low-grade fever)
Weight loss and loss of appetite
And in some people, symptoms outside of the gut, such as joint pain, skin rashes, or eye irritation, may occur.
When Are Changes in Stool an Emergency?
Not every flare requires a trip to the emergency room, but in some cases stool changes can signal a medical crisis rather than a manageable flare, says Peggy Headstrom, MD, a gastroenterologist at Gastro Health in Seattle.
According to Moss and Dr. Headstrom, you should seek immediate medical care if you experience:
Frequent diarrhea with fever, chills, weakness, or signs of dehydration such as dizziness, dry mouth, or dark urine
Large amounts of bright red blood or dark, maroon-colored stools
Severe abdominal pain
Symptoms of toxic megacolon, including significant abdominal bloating, a rapid heart rate, and worsening pain
These symptoms can be life-threatening and require urgent evaluation, Headstrom says. “I encourage people to contact their GI doctor right away if this happens. Depending on how sick they are, they may be advised to go to the emergency room,” Headstrom says.
In some instances, you should go directly to the emergency room: “If your symptoms are worsening and you feel like it is an emergency, you should head to the hospital,” Rao says.
How to Track Changes in Stool
Because stool changes are a critical marker of UC activity, keeping track of them can help you and your healthcare team spot flares early and adjust treatment quickly, Moss says.
Don’t shy away from sharing the data with your healthcare provider. “Talking about bowel movements can feel embarrassing, but it is a crucial part of managing IBD and getting the right care, so these conversations need to be treated as normal, not taboo,” he says.
You can track changes by:
Keeping a Journal Use a notebook or a smartphone app to log bowel movement frequency and urgency, rate stool consistency using the Bristol Stool Chart, and note the presence of blood or mucus, Rao says.
Taking a Photo As awkward as it may feel, gastroenterologists often find stool photos more accurate and helpful than written descriptions alone. “We do this everyday, so there’s nothing to be embarrassed about. Having a photo instead of a vague description can help us make more accurate decisions,” Rao says.
Stool Testing Doctors may order tests to measure fecal calprotectin, a protein that rises when there’s intestinal inflammation, Moss says. Establishing a baseline value and tracking trends over time can help distinguish a flare from other causes of symptoms. They may also test stool for infection, as symptoms can be similar to a flare, but treatments differ.
The Takeaway
Changes in stool are one of the most reliable ways to detect whether you’re out of remission and heading into a flare.
An increase in loose or watery stools, visible blood (even just on toilet paper), mucus or pus, and urgency can all signal active inflammation.
If symptoms escalate to heavy bleeding, severe abdominal pain, diarrhea with fever and signs of dehydration, or very frequent diarrhea, you may need to seek emergency care.
Tracking your bowel movements may help you get ahead of flares.
EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Ira Daniel Breite, MD, is a board-certified internist and gastroenterologist. He is an associate professor at the Icahn School of Medicine at Mount Sinai, where he also sees patients and helps run an ambulatory surgery center.
Dr. Breite divides his time between technical procedures, reading about new topics, and helping patients with some of their most intimate problems. He finds the deepest fulfillment in the long-term relationships he develops and is thrilled when a patient with irritable bowel syndrome or inflammatory bowel disease improves on the regimen he worked with them to create.
Breite went to Albert Einstein College of Medicine for medical school, followed by a residency at NYU and Bellevue Hospital and a gastroenterology fellowship at Memorial Sloan Kettering Cancer Center. Working in city hospitals helped him become resourceful and taught him how to interact with people from different backgrounds.
Carmen Chai is a Canadian journalist and award-winning health reporter. Her interests include emerging medical research, exercise, nutrition, mental health, and maternal and pediatric health. She has covered global healthcare issues, including outbreaks of the Ebola and Zika viruses, anti-vaccination movements, and chronic diseases like obesity and Alzheimer’s.
Chai was a national health reporter at Global News in Toronto for 5 years, where she won multiple awards, including the Canadian Medical Association award for health reporting. Her work has also appeared in the Toronto Star, Vancouver Province, and the National Post. She received a bachelor’s degree in journalism from Ryerson University in Toronto.
