Crohn's disease and ulcerative colitis: what should you know?

Crohn's disease can affect any part of the digestive tract and may involve patches of inflammation through the bowel wall. Ulcerative colitis affects the lining of the large bowel and rectum, usually starting in the rectum and extending continuously. Both conditions can have periods of active symptoms and quieter periods.

Symptoms alone cannot reliably distinguish them. Diarrhoea, urgency, abdominal pain, blood in the stool, tiredness and reduced appetite may occur with either condition. Infection, medicines and other bowel problems can mimic inflammatory bowel disease, so diagnosis uses the history, examination and appropriate tests.

Arrange a GP consultation if bowel symptoms persist, recur or include blood, night-time disturbance, weight change or marked fatigue. Bring a list of medicines and note stool pattern, pain location, fever, appetite and family history. A clinician may arrange blood or stool tests and refer you for specialist assessment.

Take prescribed treatment as directed and discuss side effects before making changes. A personalised plan may include monitoring inflammation, nutrition support and treatment adjustments. Do not rely on a symptom comparison to choose treatment, because the conditions can behave differently in the same person.

Seek urgent help for severe or rapidly worsening abdominal pain, a swollen abdomen, repeated vomiting, inability to keep fluids down, faintness, confusion, heavy rectal bleeding or high fever. Prompt assessment is also needed when diarrhoea is suddenly much more frequent than usual or you become too weak to manage normal activities.

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