Budesonide (Oral)
Indications
| Indication | Approved Population | Therapy Type | Status |
|---|---|---|---|
| Active mild-to-moderate Crohn disease (ileal/ascending colon) | Adults and children ≥8 years (>25 kg) | Induction (Entocort EC) | FDA Approved |
| Crohn disease — maintenance of clinical remission | Adults only | Maintenance up to 3 months (Entocort EC) | FDA Approved |
| Active mild-to-moderate ulcerative colitis — induction of remission | Adults | Induction up to 8 weeks (Uceris) | FDA Approved |
Oral budesonide is a topically-acting glucocorticoid designed to deliver high local anti-inflammatory activity in the gut with substantially reduced systemic steroid exposure compared to conventional corticosteroids such as prednisone. The two principal formulations (Entocort EC and Uceris) differ in their release characteristics: Entocort EC capsules dissolve at pH >5.5, targeting the ileum and ascending colon for Crohn disease, while Uceris extended-release tablets dissolve at pH ≥7, targeting the entire colon for ulcerative colitis. This distinction is clinically important and the formulations should not be used interchangeably.
Microscopic colitis (collagenous and lymphocytic) — Budesonide (Entocort EC formulation) is considered the first-line agent for induction and maintenance of microscopic colitis by AGA guidelines. Typical dose: 9 mg/day for 6–8 weeks, then taper. Evidence quality: High (multiple RCTs).
Autoimmune hepatitis — Alternative to prednisone for induction in non-cirrhotic patients intolerant of conventional corticosteroids. Evidence quality: Moderate (AASLD guidelines acknowledge role in selected patients).
IgA nephropathy — A targeted-release formulation (Tarpeyo 16 mg/day) is FDA-approved separately; however, Entocort EC has been used off-label in IgAN at various doses. Evidence quality: Moderate.
Dosing
Adult Dosing by Clinical Scenario
| Clinical Scenario | Starting Dose | Maintenance Dose | Maximum Dose | Notes |
|---|---|---|---|---|
| Crohn disease — active mild-to-moderate (ileum/ascending colon) | 9 mg once daily AM | 6 mg once daily AM | 9 mg/day | Entocort EC 3 mg capsules ×3; treat for up to 8 weeks; repeat courses allowed for recurrence Swallow whole or sprinkle on applesauce; avoid grapefruit juice |
| Crohn disease — remission maintenance | 6 mg once daily AM | 6 mg once daily AM | 6 mg/day | Entocort EC; maximum 3 months of maintenance; then attempt taper to cessation Continued therapy >3 months has not shown substantial clinical benefit |
| Ulcerative colitis — induction of remission | 9 mg once daily AM | Not FDA-approved for UC maintenance | 9 mg/day | Uceris 9 mg ER tablet; treat for up to 8 weeks; swallow whole with or without food Do not chew, crush, or break; avoid grapefruit juice |
| Microscopic colitis — induction (off-label) | 9 mg once daily AM | 3–6 mg/day (low-dose maintenance) | 9 mg/day | Entocort EC; induce for 6–8 weeks; taper by 3 mg every 2–4 weeks High relapse rate off therapy; many patients require long-term low-dose maintenance (AGA) |
| Switching from systemic corticosteroids | 9 mg once daily AM | Per indication | 9 mg/day | Begin tapering prednisolone simultaneously with starting budesonide Monitor for adrenal insufficiency and steroid withdrawal symptoms; do not stop prednisolone abruptly |
Paediatric Dosing
| Clinical Scenario | Starting Dose | Maintenance Dose | Maximum Dose | Notes |
|---|---|---|---|---|
| Crohn disease — children 8–17 years (>25 kg) | 9 mg once daily AM | 6 mg once daily for 2 weeks (taper) | 9 mg/day | Entocort EC; 8 weeks at 9 mg, then 6 mg for 2 weeks Paediatric maintenance not established; monitor growth; slightly higher systemic exposure than adults |
Entocort EC and Uceris are NOT interchangeable. Entocort EC (pH-dependent release at >5.5) delivers budesonide to the ileum and proximal colon — ideal for ileal/ileocolonic Crohn disease and microscopic colitis. Uceris (pH-dependent release at ≥7 with extended core) delivers budesonide throughout the colon — designed specifically for ulcerative colitis. Using the wrong formulation for the wrong indication compromises drug delivery to the target site.
For patients with moderate hepatic impairment (Child-Pugh Class B), consider reducing the Entocort EC dose to 3 mg once daily. Avoid use entirely in patients with severe hepatic impairment (Child-Pugh Class C), as budesonide systemic exposure is approximately 2.5-fold higher in cirrhotic patients compared to healthy volunteers.
Pharmacology
Mechanism of Action
Budesonide is a potent synthetic glucocorticoid with approximately 200-fold greater affinity for the glucocorticoid receptor than cortisol and 15-fold greater than prednisolone. Its high topical anti-inflammatory activity in the gut is paired with an intentionally high first-pass hepatic metabolism (80–90%), which dramatically limits systemic exposure. Following absorption, budesonide is rapidly and extensively biotransformed by CYP3A4 into two principal metabolites — 6β-hydroxybudesonide and 16α-hydroxyprednisolone — which have less than 1% of the glucocorticoid activity of the parent compound. This pharmacokinetic profile produces meaningful local anti-inflammatory effects in the intestinal wall while causing significantly fewer systemic steroid side effects than equipotent doses of prednisone or prednisolone.
ADME Profile
| Parameter | Value | Clinical Implication |
|---|---|---|
| Absorption | Entocort EC: Tmax 2–8 h (median 3.5 h); Cmax ~1.5 ng/mL (single dose). Uceris: Tmax 13.3 ± 5.9 h (mean); Cmax ~1.35 ng/mL. Bioavailability 9–21% | Delayed, pH-dependent release ensures topical delivery; Uceris releases distally in the colon (pH ≥7) hence later Tmax; food minimally affects AUC but delays Uceris absorption by ~2.4 h; grapefruit juice approximately doubles exposure |
| Distribution | Vd 2.2–3.9 L/kg; 85–90% plasma protein bound | Extensive tissue distribution; concentrates in intestinal wall and liver |
| Metabolism | CYP3A4 (primary); 80–90% first-pass hepatic extraction; metabolites have <1% glucocorticoid activity | CYP3A4 inhibitors (ketoconazole, ritonavir) cause up to 8-fold increase in systemic exposure; CYP3A4 inducers reduce efficacy; hepatic cirrhosis increases exposure ~2.5-fold |
| Elimination | Clearance 0.9–1.8 L/min (approaches liver blood flow); t½ 2–3.6 h; ~60% urinary excretion (metabolites), fecal elimination of remainder | High hepatic clearance drug; no dose adjustment needed for renal impairment; metabolites have negligible corticosteroid activity |
Side Effects
| Adverse Effect | Incidence | Clinical Note |
|---|---|---|
| Headache | 11–21% | Most commonly reported effect across both Entocort EC (21%) and Uceris (11.4%) trials; usually mild and self-limiting |
| Respiratory infection | 11% | Entocort EC trials; includes upper respiratory tract infections; comparable to placebo rates in many studies |
| Nausea | 5–11% | Entocort EC (11%) and Uceris (5.1%); taking medication in the morning with or after food may help |
| Adverse Effect | Incidence | Clinical Note |
|---|---|---|
| Back pain | ~7% | Entocort EC trials; not clearly dose-related |
| Dyspepsia | ~6% | Both formulations; may reflect underlying GI disease |
| Dizziness | ~5% | Entocort EC trials; distinguish from steroid-related CNS effects |
| Abdominal pain | ~5% | Both formulations; overlap with disease symptoms; Uceris upper abdominal pain 3.9% |
| Flatulence | ~5% | Both formulations; usually mild |
| Vomiting | ~5% | Entocort EC trials; similar to placebo rates |
| Fatigue | 3–5% | Both formulations; may also be a symptom of underlying adrenal suppression |
| Decreased blood cortisol | 4.3% | Uceris trials (vs 0.4% placebo); HPA suppression is dose- and duration-dependent |
| Acne | 2.4–5% | Glucocorticoid-related; more apparent at higher doses or longer duration |
| Arthralgia | 2.0% | Uceris trials; may also indicate steroid withdrawal if tapering from systemic steroids |
| Adverse Effect | Estimated Frequency | Typical Onset | Required Action |
|---|---|---|---|
| Adrenal suppression / HPA axis impairment | Common (47% abnormal ACTH at 4 wk; 79% at 8 wk with Uceris 9 mg) | Weeks; dose-dependent | Taper when discontinuing; provide stress-dose steroids during surgery or acute illness; do not stop abruptly |
| Serious infections (varicella, measles, TB reactivation, fungal) | Rare | Any time during immunosuppression | Discontinue or hold budesonide; initiate appropriate anti-infective therapy; avoid live vaccines during treatment |
| Anaphylaxis / severe hypersensitivity | Very rare (postmarketing) | Any time | Discontinue permanently; emergency epinephrine; the drug is contraindicated after anaphylaxis |
| Hepatitis B reactivation | Rare | Weeks to months | Screen for HBV before starting immunosuppressive therapy; consult hepatology; consider antiviral prophylaxis |
| Osteoporosis / vertebral fractures (prolonged use) | Uncommon with short courses | Months of cumulative use | Assess bone density if prolonged or repeated courses anticipated; calcium and vitamin D supplementation |
| Growth suppression (paediatric) | Reported | Cumulative exposure | Monitor height and weight regularly; minimise duration and use lowest effective dose |
In the Uceris UC trials, the overall incidence of glucocorticoid-related effects (mood changes, sleep disturbance, insomnia, acne, moon face, fluid retention, hirsutism) was 10.2% with budesonide 9 mg versus 10.5% with placebo at 8 weeks, indicating no clinically significant difference during short-term induction. However, HPA axis suppression is dose- and duration-dependent: at 8 weeks with Uceris 9 mg, 79% of patients had an abnormal response to ACTH stimulation testing. This underscores the importance of limiting treatment duration and tapering appropriately.
Drug Interactions
Budesonide is extensively metabolised by CYP3A4. Its interaction profile is dominated by agents that inhibit or induce this enzyme. Because systemic budesonide levels are normally very low, the drug is unlikely to affect the metabolism of co-administered CYP3A4 substrates.
Monitoring
-
Signs of hypercorticism
Each visit
Routine Assess for moon face, acne, weight gain, striae, mood disturbance, insomnia, fluid retention, and glucose intolerance. Risk increases with prolonged or repeated courses. -
Adrenal function (morning cortisol or ACTH stimulation test)
If prolonged therapy, switching from systemic steroids, or symptoms of adrenal insufficiency
Trigger-based HPA suppression is common at 8 weeks (79% abnormal ACTH response with Uceris 9 mg). Check before surgery or during acute illness to determine need for stress-dose steroids. -
Blood glucose
Baseline and periodically in at-risk patients
Routine Corticosteroids can unmask latent diabetes or worsen glycaemic control. Pay particular attention to patients with pre-existing diabetes or family history. -
Bone density (DEXA)
If prolonged or repeated courses anticipated
Trigger-based In a 12-month Uceris maintenance study, 77% of budesonide 6 mg patients maintained normal bone density scans. Consider baseline DEXA for patients likely to require chronic low-dose budesonide (e.g., microscopic colitis). -
Growth velocity (paediatric)
At each clinic visit
Routine Monitor weight and height regularly in children receiving budesonide; growth suppression has been reported with systemic exposure from oral budesonide. -
Hepatitis B screening
Before initiation of immunosuppressive therapy
Trigger-based HBV reactivation can occur with corticosteroid therapy. Screen HBsAg and anti-HBc before starting prolonged budesonide. -
Intraocular pressure / cataract screen
If prolonged use or symptoms develop
Trigger-based Long-term corticosteroid use increases risk of glaucoma and posterior subcapsular cataracts; ophthalmology referral if visual changes occur.
Contraindications & Cautions
Absolute Contraindications
- Hypersensitivity to budesonide or any excipient in the formulation
- Prior anaphylaxis to any budesonide-containing product
Relative Contraindications (Specialist Input Recommended)
- Severe hepatic impairment (Child-Pugh C) — systemic exposure increased ~2.5-fold; avoid use
- Active systemic fungal infection — corticosteroids may exacerbate
- Known Strongyloides infestation — risk of disseminated hyperinfection
- Cerebral malaria — corticosteroids have been associated with worse outcomes
- Ocular herpes simplex — risk of corneal perforation
Use with Caution
- Moderate hepatic impairment (Child-Pugh B) — consider dose reduction to 3 mg/day (Entocort EC); monitor for hypercorticism
- Diabetes mellitus — corticosteroids may worsen glycaemic control
- Hypertension, osteoporosis, peptic ulcer, glaucoma, cataracts — conditions where glucocorticoids may have unwanted effects
- Patients being transferred from systemic corticosteroids — risk of adrenal insufficiency and steroid withdrawal; taper the previous corticosteroid simultaneously
- Pregnancy — animal data show fetal harm at subclinical doses; use only if benefit justifies risk
- Active or latent tuberculosis — risk of reactivation; consider chemoprophylaxis during prolonged therapy
Corticosteroids, including oral budesonide, suppress immune function and increase the risk of new infections, disseminated infections, and reactivation of latent infections (including tuberculosis and hepatitis B). Varicella and measles can be fatal in immunosuppressed patients. Prolonged use causes dose-dependent HPA axis suppression; supplemental systemic steroids are required during physiological stress in patients with impaired adrenal function. Abrupt discontinuation may precipitate adrenal crisis.
Patient Counselling
Purpose of Therapy
Budesonide is a type of steroid that works directly on the lining of the gut to reduce inflammation, with far fewer whole-body side effects than traditional steroid tablets like prednisone. It is used to control flare-ups of Crohn disease or ulcerative colitis. It does not provide immediate symptom relief and typically takes several days to begin working.
How to Take
Take budesonide in the morning. Swallow capsules or tablets whole — do not chew, crush, or break them. If you cannot swallow the Entocort EC capsule, you may open it and sprinkle the granules onto a tablespoon of cool applesauce; swallow the mixture within 30 minutes without chewing, followed by a full glass of water. Avoid eating grapefruit or drinking grapefruit juice while on this medication.
Sources
- ENTOCORT EC (budesonide) delayed-release capsules — Full Prescribing Information. Padagis / FDA. Revised June 2024. accessdata.fda.gov Primary regulatory source for Crohn disease dosing, adverse reactions table, paediatric use, and pharmacokinetics of the delayed-release capsule formulation.
- UCERIS (budesonide) extended-release tablets — Full Prescribing Information. Salix Pharmaceuticals / FDA. Revised June 2024. accessdata.fda.gov Regulatory source for UC indication, adverse event incidence from placebo-controlled trials, glucocorticoid-related effects data, and ACTH stimulation test results.
- Greenberg GR, Feagan BG, Hanauer SB, et al. Oral budesonide for active Crohn’s disease. N Engl J Med. 1994;331(13):836-841. doi:10.1056/NEJM199409293311303 Pivotal RCT demonstrating budesonide 9 mg superiority over placebo for inducing remission in mild-to-moderate ileal/ileocolonic Crohn disease.
- Sandborn WJ, Travis S, Moro L, et al. Once-daily budesonide MMX extended-release tablets induce remission in patients with mild to moderate ulcerative colitis: results from the CORE I study. Gastroenterology. 2012;143(5):1218-1226.e2. doi:10.1053/j.gastro.2012.08.003 Phase III trial (CORE I) supporting Uceris 9 mg for UC induction; provided basis for FDA approval.
- Miehlke S, Madisch A, Bethke B, et al. Budesonide for the treatment of collagenous colitis: a randomized, double-blind, placebo-controlled, multicenter trial. Gastroenterology. 2002;123(4):978-984. doi:10.1053/gast.2002.36042 Key RCT establishing budesonide efficacy in collagenous (microscopic) colitis; foundation for off-label first-line recommendation.
- Rutgeerts P, Lofberg R, Malchow H, et al. A comparison of budesonide with prednisolone for active Crohn’s disease. N Engl J Med. 1994;331(13):842-845. doi:10.1056/NEJM199409293311304 Head-to-head comparison demonstrating comparable efficacy to prednisolone with significantly fewer glucocorticoid-related side effects.
- Lichtenstein GR, Loftus EV, Isaacs KL, et al. ACG Clinical Guideline: Management of Crohn’s Disease in Adults. Am J Gastroenterol. 2018;113(4):481-517. doi:10.1038/ajg.2018.27 Current ACG guideline positioning oral budesonide as first-line induction therapy for mild-to-moderate ileal/ileocolonic Crohn disease.
- Rubin DT, Ananthakrishnan AN, Siegel CA, et al. ACG Clinical Guideline: Ulcerative Colitis in Adults. Am J Gastroenterol. 2019;114(3):384-413. doi:10.14309/ajg.0000000000000152 ACG guideline supporting budesonide MMX (Uceris) for mild-to-moderate UC when mesalamine alone is insufficient.
- Nguyen GC, Bernstein CN, Bitton A, et al. AGA Clinical Practice Update on the Management of Microscopic Colitis. Gastroenterology. 2022;163(2):574-586. doi:10.1053/j.gastro.2022.04.015 AGA update recommending budesonide as first-line therapy for induction and maintenance of microscopic colitis.
- Edsbacker S, Andersson T. Pharmacokinetics of budesonide (Entocort EC) capsules for Crohn’s disease. Clin Pharmacokinet. 2004;43(12):803-821. doi:10.2165/00003088-200443120-00003 Comprehensive pharmacokinetic review covering absorption, distribution, CYP3A4 metabolism, first-pass elimination, and special populations.
- Sherlock ME, Seow CH, Steinhart AH, Griffiths AM. Oral budesonide for induction of remission in ulcerative colitis. Cochrane Database Syst Rev. 2010;(10):CD007698. doi:10.1002/14651858.CD007698.pub2 Cochrane systematic review assessing oral budesonide efficacy and safety for UC induction across formulations.
- Plosker GL, Croom KF. Budesonide (Entocort EC capsules): a review of its therapeutic use in the management of active Crohn’s disease in adults. Drugs. 2002;62(15):2263-2282. doi:10.2165/00003495-200262150-00015 Narrative review summarising clinical trial data, tolerability profile, and positioning of Entocort EC relative to prednisolone and mesalamine.