What should you know about acute severe ulcerative colitis?

It is a particularly intense flare of inflammation in the colon. Frequent bloody diarrhoea may occur alongside abdominal pain, fever, a fast heartbeat, marked weakness or dehydration. Hospital care allows the team to treat the inflammation quickly and watch for complications.

Ulcerative colitis causes inflammation and ulcers in the lining of the rectum and colon. In an acute severe episode, bowel symptoms are accompanied by signs that the inflammation is affecting the body more widely. Blood loss, fluid loss and reduced food intake can contribute to anaemia, dehydration and changes in body salts.

Clinicians assess severity using your bowel frequency, bleeding, pulse, temperature, examination findings and test results. Blood and stool tests can measure inflammation, check for anaemia and look for infection. Imaging may be needed to check whether the colon is becoming dangerously swollen or whether another complication is developing.

Treatment commonly starts with corticosteroid medicine given into a vein. Fluids and correction of body salts may also be needed. The team reviews symptoms, observations, blood results and abdominal findings regularly rather than waiting until the end of a treatment course.

A gastroenterologist and colorectal surgeon may assess you early. Surgical involvement does not mean an operation is certain; it means options can be discussed without delay if inflammation does not improve or a complication appears. If intravenous steroids are unsuitable or are not controlling the flare, the team may consider another inflammation-suppressing medicine, such as infliximab or ciclosporin, or surgery to remove the colon. The choice depends on your condition, previous medicines, test results and preferences.

Do not start, stop or increase steroids, immune-suppressing medicines or anti-diarrhoeal medicines on your own during a severe flare. Bring an up-to-date medicines list and tell the hospital team about allergies, recent antibiotics, infections and previous responses to ulcerative colitis treatments.

If you have ulcerative colitis and develop frequent bloody diarrhoea with fever, a racing heartbeat, worsening abdominal pain, pronounced weakness, dizziness or difficulty keeping fluids down, contact your gastroenterology team urgently or go to an emergency department. Do not wait for a routine appointment.

Call emergency services for severe or rapidly worsening abdominal pain, a swollen or very tender abdomen, heavy or continuous rectal bleeding, fainting, confusion, breathing difficulty or collapse. These features can accompany major blood loss, severe dehydration, a markedly swollen colon or a bowel perforation.

Ask how the team is measuring your response, whether infection has been excluded and what changes would trigger rescue medicine or surgery. It can also help to ask which medicine side effects need monitoring, what food and fluids are suitable now, and what maintenance treatment and follow-up may be needed after discharge.