Ulcerative colitis: symptoms, diagnosis and care

Ulcerative colitis is a long-term inflammatory bowel disease that causes inflammation and ulcers in the colon.

The inflammation usually begins in the rectum and may extend through part or all of the large bowel. It is not caused by a person doing something wrong, and it is not the same as irritable bowel syndrome. Symptoms can come and go, with quieter periods between flares.

Ulcerative colitis commonly presents with diarrhoea, blood or mucus in stool, urgency to open the bowels, abdominal pain, tiredness and loss of appetite. Some people experience unintentional weight loss during active inflammation. The pattern and severity vary between people and across flares.

Contact a clinician promptly for increasing rectal bleeding, severe abdominal pain, fever, repeated vomiting, marked weakness, dehydration or a swollen abdomen. These features require assessment even if you have had similar bowel symptoms before.

The exact cause is not fully understood. Ulcerative colitis involves an inappropriate immune response in the bowel in people with a genetic susceptibility. Gut microbes and environmental factors may influence the condition, but it is not contagious. Stress does not cause ulcerative colitis, although it can make coping with symptoms harder.

Inflammation may remain confined to the rectum or involve more of the colon. Flares can alternate with remission, when symptoms are minimal or absent. Regular review helps clinicians adjust treatment to inflammation rather than relying only on how someone feels, since bowel healing and symptoms do not always change together.

Ulcerative colitis can occur at different ages. Having a close relative with inflammatory bowel disease may raise susceptibility, but family history does not determine whether someone will develop it. New bowel symptoms still need assessment on their own merits.

Diagnosis combines symptom history, examination, blood tests, stool tests and inspection of the bowel with a flexible camera test. Tissue samples may be taken during the camera test to distinguish ulcerative colitis from infection and other causes of bowel inflammation. The extent of inflammation helps shape treatment and follow-up.

Treatment aims to settle active inflammation, maintain remission and prevent complications. Depending on extent and severity, options may include anti-inflammatory bowel medicines, medicines that change immune activity, targeted medicines, short-term steroids for a flare, and surgery when medical treatment does not control disease or complications occur. The specialist weighs benefits, side effects, pregnancy plans and monitoring needs with you.

Keep taking maintenance medicine during remission unless the treating team advises otherwise. A symptom and food diary can help identify personal triggers for discomfort, though food does not replace anti-inflammatory treatment. During a flare, ask about hydration, nutrition, work or school adjustments and which medicines to avoid. Tell the care team before using anti-inflammatory pain medicines, supplements or herbal products.

Active disease can lead to dehydration, anaemia and nutritional difficulties. Severe inflammation can rarely cause the colon to widen dangerously or perforate. Long-standing colonic inflammation also changes how clinicians plan bowel surveillance, so attend the follow-up schedule recommended for your individual extent and history.

There is no known way to prevent ulcerative colitis completely. Taking treatment consistently, reporting a flare early, avoiding smoking initiation, keeping vaccinations and routine care up to date, and discussing travel or pregnancy plans with the team can reduce avoidable disruption.

A GP can assess new bowel symptoms and arrange initial tests. Gastroenterology teams diagnose and manage ulcerative colitis, with dietitians, specialist nurses and colorectal surgeons involved when needed. Seek urgent care for severe symptoms rather than waiting for a routine appointment.