Dexamethasone and ulcerative colitis: what to know

Ulcerative colitis causes inflammation and sores in the lining of the large bowel. A corticosteroid such as dexamethasone can calm immune activity, which may ease diarrhoea, abdominal pain, urgency, and rectal bleeding during an active flare. It is generally considered a short-term flare treatment rather than a maintenance medicine. It does not remove the underlying tendency for ulcerative colitis to return.

Steroids can affect sleep, mood, appetite, blood glucose, blood pressure, and infection response. The risk depends on the dose, route, duration, and your health history. Do not stop a prescribed course suddenly without advice, because the body may need time to adjust.

Take dexamethasone exactly as prescribed and tell the prescriber about diabetes, high blood pressure, osteoporosis, glaucoma, previous mental-health reactions to steroids, or current infections. Ask whether it should be taken with food and what tapering plan applies. Keep a record of bowel frequency, bleeding, pain, fever, and any new side effects.

Arrange a review to confirm whether symptoms are improving and to plan a longer-term ulcerative colitis treatment. A GP Consultation can help coordinate assessment, while tests may be arranged if the pattern changes. Avoid starting anti-inflammatory medicines or leftover steroids without medical advice.

Seek urgent medical help for severe or worsening abdominal pain, a swollen abdomen, repeated vomiting, heavy rectal bleeding, faintness, confusion, high fever, or inability to keep fluids down. Contact your clinician promptly if diarrhoea or bleeding is increasing, or if dexamethasone causes marked mood change, severe weakness, vision changes, or signs of infection such as fever and a persistent cough.

Ask: Is dexamethasone suitable for this flare? How long should I take it, and how will the dose be reduced? Which symptoms mean I need same-day help? Do I need blood tests, stool testing, or a gastroenterology review? What treatment will help prevent another flare?