| Drug | Class | Adult | Paediatric | Notes |
|---|---|---|---|---|
| Mesalazine (5-ASA)[1] | Aminosalicylate | Mesalazine 2.4–4.8 g PO daily for induction; 2–3 g daily for maintenance; topical 1–4 g rectal for proctitis/distal disease | 50–100 mg/kg/day | First-line for mild-moderate UC; minimal role in Crohn's |
| Prednisolone (induction)[1] | Glucocorticoid | 40 mg PO once daily, taper over 8 weeks; IV methylprednisolone 60 mg daily for severe disease | 1–2 mg/kg/day | Induction only; not for maintenance — long-term toxicity; budesonide MMX for distal UC, ileal Crohn's |
| Azathioprine or 6-mercaptopurine[1] | Thiopurine immunomodulator | Azathioprine 2–2.5 mg/kg/day; 6-MP 1–1.5 mg/kg/day; check TPMT before starting | Same per kg | Steroid-sparing maintenance in moderate disease; combination with TNF inhibitor reduces immunogenicity |
| Infliximab[1] | Anti-TNF biologic | 5 mg/kg IV at 0, 2, 6 weeks then every 8 weeks; combination with immunomodulator preferred | Same per kg | Moderate-severe UC and Crohn's; rescue therapy in severe acute UC; pre-treatment HBV/TB/strongyloides screen |
| Vedolizumab or ustekinumab[1] | Gut-selective integrin / IL-12/23 inhibitor | Vedolizumab 300 mg IV at 0, 2, 6 weeks then q8w; ustekinumab 6 mg/kg IV induction then 90 mg SC q8w | — | Alternative biologics; vedolizumab gut-selective, less infection risk; ustekinumab effective in Crohn's |
| Tofacitinib or upadacitinib (UC)[1] | JAK inhibitor | Tofacitinib 10 mg PO BD induction × 8 weeks then 5 mg BD; upadacitinib 45 mg PO daily induction × 8 weeks then 15–30 mg daily | — | Moderate-severe UC; small-molecule oral; specialist; cardiovascular and thrombotic risk monitoring per ORAL Surveillance |
Diagnosis and treatment of ulcerative colitis and Crohn's disease per current ECCO/ACG guidance — biologics and small molecules in moderate-severe disease.