Ulcerative colitis and a stomach bug: what to know

Both problems may cause diarrhoea, abdominal cramps, urgency, nausea, and reduced appetite. A stomach bug often begins suddenly after contact with someone unwell or unsafe food and may include vomiting or fever. A colitis flare can bring more frequent stools, urgency, blood or mucus, and a pattern similar to previous flares. These clues overlap, and infection can also trigger worsening bowel inflammation. Do not assume that every change is a flare or that every flare is an infection.

Contact your IBD team or GP promptly if symptoms are new, unusually severe, or different from your usual pattern. Sip fluids regularly; oral rehydration advice may be useful if diarrhoea or vomiting is significant. Eat small, simple meals as tolerated and wash hands carefully to reduce spread. Continue prescribed medicines unless a clinician tells you otherwise, but ask before taking anti-diarrhoeal products or antibiotics. Record stool changes, fever, vomiting, pain, and recent sick contacts.

Seek urgent medical help for severe or increasing abdominal pain, a swollen abdomen, repeated vomiting, faintness, confusion, very little urine, or inability to keep fluids down. Prompt assessment is also needed for heavy rectal bleeding, high fever, or rapidly worsening diarrhoea. People taking immune-suppressing treatment may need earlier advice because infection can become more serious and treatment choices may differ.

Could this be infection, a flare, or both? Do I need stool tests or blood tests? How should I manage my regular medicine while unwell? Which fluids and medicines are suitable for me? What signs mean I should attend urgent care?