Paying attention to changes in bowel movements is a crucial part of managing ulcerative colitis (UC), a chronic inflammatory bowel disease. For the over one million Americans living with UC, understanding what their stool looks like during a flare can provide valuable insights into disease activity and help guide treatment decisions. Recognizing the subtle—and not-so-subtle—shifts in stool consistency, color and the presence of blood or mucus can empower individuals to proactively communicate with their healthcare team and potentially prevent more serious complications.
Alan Moss, MD, chief scientific officer at the Crohn’s &. Colitis Foundation and a professor of gastroenterology at Boston University’s Chobanian & Avedisian School of Medicine, emphasizes the importance of self-monitoring. “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. He stresses that “no amount of visible blood, persistent diarrhea, or significant change from your ‘usual’ is too minor to mention” to your doctor.
Ulcerative colitis causes inflammation and ulcers in the lining of the large intestine and rectum. When this inflammation flares up, it significantly impacts bowel function, leading to noticeable changes in stool. These changes aren’t simply unpleasant; they’re signals that the disease is active and may require adjustments to medication or other therapies. Understanding these signals is key to effective disease management and maintaining quality of life.
What Does a UC Flare Gaze Like in Your Stool?
One of the most common indicators of a UC flare is a change in stool consistency. According to Dr. Moss, diarrhea or loose stools are frequently experienced. Instead of formed stools, individuals may experience mushy or completely liquid bowel movements, often categorized as types 5 to 7 on the Bristol Stool Chart. This shift in consistency is often accompanied by increased urgency and frequency of bowel movements, potentially occurring multiple times a day.
Beyond consistency, the presence of blood in the stool is a significant sign of active ulcerative colitis. Supriya Rao, MD, a gastroenterologist and spokesperson for the American Gastroenterological Association, notes that “there is no amount of blood that is considered normal in UC, even if it’s just on toilet paper.” The color and appearance of the blood can offer clues about the location of inflammation. Bright red blood typically indicates inflammation in the rectum or lower colon, while darker blood may suggest more extensive disease higher up in the digestive tract. Blood can appear mixed throughout the stool, coating it, or solely on toilet paper after wiping, and any amount warrants discussion with a physician.
The presence of mucus and pus in stool is another indicator of inflammation. The colon naturally produces mucus to protect its lining, but during a UC flare, increased inflammation leads to excessive mucus production. This excess mucus may appear as clear, white, or yellowish jellylike strands. Seeing yellow or green mucus or pus can also signal an infection, according to Dr. Rao.
Tenesmus and Other Warning Signs
Tenesmus, the persistent sensation of needing to have a bowel movement even when the bowels are empty, is a common and often distressing symptom experienced by up to 30 percent of people with inflammatory bowel disease. Dr. Rao explains that “tenesmus usually means the disease is no longer fully controlled.” This sensation can be accompanied by cramping and discomfort, significantly impacting daily life.
In addition to these core symptoms, several other red flags should prompt immediate communication with a gastroenterology team. These include a rising sense of urgency, nocturnal bowel movements (waking up at night to use the bathroom), changes in stool odor—particularly a foul smell which can indicate malabsorption or infection, such as Clostridioides difficile—abdominal pain, rectal pain, fatigue, fever, and unexplained weight loss or loss of appetite.
UC can sometimes manifest with symptoms outside of the digestive system. Individuals may experience joint pain, skin rashes, or eye irritation. These extraintestinal manifestations can provide valuable clues about the overall disease activity and the necessitate for treatment adjustments.
What to Do If You Notice Changes
If you have been diagnosed with ulcerative colitis and experience any of the changes described above, it’s crucial to contact your gastroenterology team promptly. Detailed information about stool patterns—frequency, consistency, presence of blood or mucus, urgency, and any associated symptoms—can help your doctor assess the severity of the flare and tailor treatment accordingly. Keeping a symptom journal can be a helpful way to track these changes and provide accurate information to your healthcare provider.
Early intervention is key to managing UC flares effectively and preventing long-term complications. By being vigilant about monitoring bowel health and communicating openly with your doctor, individuals with ulcerative colitis can take control of their disease and maintain a better quality of life.
Disclaimer: The information provided in this article is intended for general knowledge and informational purposes only, and does not constitute medical advice. It is essential to consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.
The Crohn’s & Colitis Foundation offers a wealth of resources for individuals living with UC and their families. For more information and support, visit their website. If you found this information helpful, please share it with others who may benefit from it.
