Corticosteroid — Locally Acting (GI) Pregnancy: Compatible with caution — inhaled/rectal budesonide is preferred over systemic steroids in pregnancy for IBD. Oral modified-release budesonide: use only if clearly needed. First-pass mechanism reduces foetal exposure. ECCO recommends continuing if disease control requires it — disease activity is more harmful than drug. BNF 90.

Budesonide (Oral / Rectal)

Brand names: Entocort, Budenofalk, Cortiment

Adult dose

Dose: Crohn's disease (ileal/ileocaecal): 9 mg once daily in the morning. Microscopic colitis: 9 mg once daily for 8 weeks, then taper. Autoimmune hepatitis: 6–9 mg/day (off-label, in combination with azathioprine)

Route: Oral (modified-release capsules/granules)

Frequency: Once daily (Entocort) or in divided doses (Budenofalk granules)

Max: 9 mg/day

Entocort 3 mg capsules: take 3 capsules once daily before breakfast. Budenofalk 3 mg granules: one sachet three times daily. Cortiment 9 mg: once daily for microscopic colitis (MMX modified-release, colonic delivery). All formulations undergo extensive first-pass metabolism — 90% of absorbed budesonide is inactivated in the liver, resulting in systemic exposure ~10-fold less than prednisolone. Source: BNF 90; ECCO Crohn's Guidelines; NICE NG129.

Paediatric dose

Dose: Crohn's disease: 0.45 mg/kg/day (max 9 mg/day). Entocort licensed from 8 years mg/day/kg

Route: Oral

Frequency: Once daily

Max: 9 mg/day

Entocort licensed in paediatric Crohn's disease (mild-moderate, ileocaecal) from 8 years. Budenofalk granules: licensed from 8 years. Dose: 9 mg once daily (or weight-adjusted 0.45 mg/kg/day). Source: BNF for Children 2024; ECCO-ESPGHAN Paediatric IBD Guidelines.

Dose adjustments

Renal

No dose adjustment required. Budesonide is not renally excreted to a clinically significant extent.

Hepatic

Significant hepatic impairment: USE WITH CAUTION — first-pass metabolism is reduced in hepatic impairment, increasing systemic budesonide exposure and HPA-axis suppression risk. Contraindicated in severe cirrhosis for non-hepatic indications; paradoxically used in autoimmune hepatitis (specialist only) where systemic steroid-sparing is desired. Avoid in portal hypertension — portosystemic shunts bypass first-pass metabolism → significant systemic exposure.

Paediatric weight-based calculator

Patient weight (kg)

Clinical pearls

First-pass advantage — the key mechanism: budesonide undergoes 90% hepatic first-pass metabolism to inactive metabolites. This means 9 mg oral budesonide produces systemic cortisol-equivalent exposure of only ~1 mg prednisolone — hence dramatically fewer systemic steroid side effects while delivering therapeutic concentrations to the ileocaecal mucosa (Entocort) or colon (Cortiment).
Crohn's disease — induction only: budesonide 9 mg is effective for mild-moderate ileocaecal Crohn's but NOT for maintenance remission. ECCO guidelines: use for induction only (≤8 weeks at 9 mg), then taper 6 mg × 2 weeks → 3 mg × 2 weeks → stop. Not superior to prednisolone for severe disease.
Microscopic colitis (Cortiment): budesonide MMX (Cortiment 9 mg) is first-line treatment for collagenous and lymphocytic colitis. NICE NG129 recommends 8-week course. Relapse common — repeat courses or low-dose maintenance 3–6 mg used in practice. Stop NSAIDs, PPIs, SSRIs (common triggers).
Autoimmune hepatitis — specialist use: budesonide 6–9 mg + azathioprine as alternative to prednisolone + azathioprine in non-cirrhotic AIH (NEJM 2010 Manns et al.). AVOID in cirrhotic AIH — portosystemic shunts bypass first-pass → full systemic steroid exposure without benefit of reduced side effects.
CYP3A4 inhibitor warning: grapefruit juice doubles budesonide AUC. Clarithromycin or itraconazole can increase systemic budesonide 6–10 fold, causing iatrogenic Cushing's syndrome within days. Always screen for CYP3A4 inhibitors before prescribing. Source: BNF 90; ECCO IBD Guidelines 2023; NICE NG129 Microscopic Colitis.

Contraindications

Systemic fungal infections
Live vaccines (during high-dose or prolonged use)
Primary treatment of active severe UC or Crohn's with systemic features (use systemic corticosteroids instead)
Hepatic cirrhosis / portal hypertension (for non-hepatic indications): portosystemic shunts bypass first-pass — systemic exposure increases dramatically
Hypersensitivity to budesonide

Side effects

HPA axis suppression (less than systemic steroids — but dose-dependent; 9 mg for >8 weeks risks adrenal suppression)
Moon face, weight gain, acne (milder than prednisolone due to high first-pass metabolism)
Osteoporosis (prolonged use — less than systemic steroids but calcium/vitamin D supplementation recommended if >3 months)
Raised intraocular pressure, posterior subcapsular cataracts (prolonged use)
Hyperglycaemia (less than systemic steroids)
Cushing's syndrome features (rare at recommended doses — more likely in hepatic impairment or CYP3A4 inhibitor co-administration)

Interactions

Strong CYP3A4 inhibitors (clarithromycin, itraconazole, grapefruit juice): significantly increase budesonide plasma concentrations by reducing first-pass metabolism — risk of Cushing's syndrome and adrenal suppression. Avoid or reduce budesonide dose
Strong CYP3A4 inducers (rifampicin, carbamazepine): reduce budesonide levels — loss of efficacy
Live vaccines: avoid during immunosuppressive doses
Antacids, proton pump inhibitors: may alter dissolution of Entocort (pH-dependent release) — separate by at least 2 hours

Monitoring

Clinical response at 4–8 weeks (stool frequency, CRP, faecal calprotectin in Crohn's)
Adrenal function if prolonged use or CYP3A4 inhibitor prescribed concomitantly (morning cortisol)
Bone mineral density (DEXA) if treatment >3 months — consider calcium + vitamin D supplementation
Blood glucose in diabetic patients
Blood pressure
Intraocular pressure annually if prolonged use (glaucoma risk)

Reference: BNFc; BNF 90; BNF for Children 2024; ECCO Crohn's Disease Guidelines 2023; NICE NG129 (Microscopic Colitis); Manns et al. Gastroenterology 2010 (AIH budesonide trial); MHRA SPC Entocort / Cortiment. Verify against your local formulary and the latest BNF before prescribing.

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways