Idiopathic ulcerative colitis

Ulcerative colitis affects the inner lining of the colon and rectum. Inflammation can cause diarrhoea, blood or mucus in stool, urgency, abdominal pain, tiredness and reduced appetite. Symptoms often change over time, with quieter periods and flares.

Idiopathic means that no single external cause explains the inflammation. The diagnosis is based on the pattern of symptoms, examination, stool tests, blood tests and sometimes a camera examination with tissue samples. Other causes of bowel symptoms may need to be excluded.

Take prescribed anti-inflammatory or immune-targeting treatment as directed, even when symptoms settle if your clinician advises ongoing treatment. Keep a record of stool frequency, bleeding, pain, temperature and medicines so changes are easier to describe.

Drink regularly during diarrhoea and ask about nutrition if appetite or weight changes. Do not rely on restrictive diets or anti-diarrhoeal medicines during a flare without advice. A GP consultation can arrange assessment, while specialist follow-up may guide longer-term treatment and bowel monitoring.

Seek urgent care for heavy or persistent rectal bleeding, severe or increasing abdominal pain, a swollen abdomen, repeated vomiting, fever with a flare, faintness or inability to keep fluids down. Contact your clinician promptly when diarrhoea or bleeding is worsening despite your plan.

Ask which part of the bowel is affected, how treatment will be monitored, what to do during a flare and which medicines need review. Discuss vaccinations, nutrition, bone health and when colorectal cancer screening or surveillance is appropriate for you.