What is the first line therapy for microscopic colitis?

First-Line Therapy for Microscopic Colitis

Budesonide 9 mg once daily is the first-line therapy for microscopic colitis, with a strong recommendation based on high-quality evidence showing superior efficacy over all other treatments. 1, 2

Primary Treatment Recommendation

Budesonide should be prescribed at 9 mg daily for 6-8 weeks as induction therapy for all patients with symptomatic microscopic colitis. 3, 2 This recommendation applies equally to both subtypes—collagenous colitis and lymphocytic colitis—as treatment approaches are identical. 4, 5

The American Gastroenterological Association provides a strong recommendation with high-quality evidence that budesonide is superior to mesalamine for inducing clinical remission, with patients nearly twice as likely to achieve both clinical and histological remission compared to mesalamine. 1 Additionally, budesonide demonstrates more than 2.5-fold greater likelihood of achieving clinical remission compared to no treatment (relative risk 2.52,95% CI 1.45-4.4). 1

Key Advantages of Budesonide

• Once-daily dosing improves adherence compared to alternatives requiring multiple daily doses 1
• Favorable safety profile with low systemic bioavailability and minimal serious adverse events 1
• Superior efficacy with significantly higher clinical remission rates after 8 weeks compared to mesalamine (P=0.003) 6
• Lower adverse event incidence compared to mesalamine (P=0.002) 6

Alternative First-Line Options (When Budesonide Not Feasible)

If budesonide therapy is not feasible due to contraindications, cost concerns, or patient preference, consider these alternatives in descending order of recommendation strength:

1. Mesalamine (Second Choice)

• Dose: 3-4 g daily 1
• Evidence level: Conditional recommendation, moderate quality evidence 1
• Use when: Budesonide contraindicated or patient has strong preference against corticosteroids 1
• Important caveat: Costs are similar between mesalamine and budesonide, so cost should not be the determining factor between these two options 1

2. Bismuth Salicylate (Third Choice)

• Dose: 8-9 tablets daily divided three times daily 1
• Evidence level: Conditional recommendation, low quality evidence 1
• Use when: Contraindications to corticosteroids exist or cost is prohibitive 1
• Major limitation: Significant pill burden in elderly patients who typically take multiple medications 1

3. Prednisolone/Prednisone (Fourth Choice)

• Dose: 40 mg daily with gradual taper 1
• Evidence level: Conditional recommendation, very low quality evidence 1
• Use when: Cost of budesonide is prohibitive, as prednisolone is considerably less expensive 1
• Critical warning: Significant risk of adverse events with systemic corticosteroids; should not be first-line therapy in most cases 1

Essential Adjunctive Measures

Before or concurrent with pharmacologic therapy, identify and discontinue potential triggering medications: 2, 7

• Nonsteroidal anti-inflammatory drugs (NSAIDs)
• Proton pump inhibitors (PPIs)
• Selective serotonin reuptake inhibitors (SSRIs)
• Ranitidine
• Statins

Loperamide can be used for immediate symptomatic relief as an adjunct to definitive therapy. 5

Tapering and Maintenance Considerations

• After 6-8 weeks of induction therapy, taper budesonide over 1-2 weeks rather than abrupt discontinuation 3
• For patients with symptom recurrence after discontinuation, maintenance therapy with budesonide is strongly recommended 3, 2
• Maintenance dosing: Start at 6 mg daily and taper to the lowest effective dose (potentially 3 mg daily or 3 mg alternating with 6 mg daily) 3, 2
• Duration: Consider cessation after 6-12 months of maintenance therapy 3, 2
• Monitoring: Screen for bone loss with prolonged use beyond 6 months, as budesonide may predispose to osteoporosis 3, 2

Common Pitfalls to Avoid

• Do not routinely perform colonoscopy to assess histological response unless patients have residual symptoms after treatment, which may suggest coexisting conditions 1
• Do not use combination therapy with cholestyramine and mesalamine—it provides no incremental benefit over mesalamine alone 1, 2
• Do not use probiotics or Boswellia serrata—both have conditional recommendations against their use due to lack of efficacy 1, 2
• Do not use budesonide for long-term maintenance beyond 6-12 months without careful monitoring due to potential adverse effects 3