What is the recommended treatment for a patient with microscopic colitis, considering their medical history and potential contributing factors such as nonsteroidal anti-inflammatory drug (NSAID) use?

Treatment for Microscopic Colitis

Budesonide 9 mg daily for 6-8 weeks is the first-line treatment for symptomatic microscopic colitis, with strong evidence demonstrating superior efficacy in inducing clinical remission and improving quality of life. 1, 2

Initial Management Steps

Identify and Discontinue Triggering Medications

• Stop NSAIDs, proton pump inhibitors, and SSRIs when clinically feasible, as these medications are commonly associated with microscopic colitis, though recent evidence has challenged the strength of this association 2, 3
• Medication discontinuation alone may lead to symptom resolution in some patients, though direct evidence of efficacy is limited 2, 4
• Consider eliminating caffeine and lactose from the diet, though evidence for this intervention is not robust 4

Assess Disease Severity to Guide Treatment Choice

For mild symptoms:

• Antidiarrheal agents such as loperamide or bismuth subsalicylate may be sufficient, though they appear largely ineffective in most patients with microscopic colitis 4, 3
• Approximately 38% of patients achieve spontaneous remission with no treatment or simple antidiarrheals, with male gender being the only factor associated with spontaneous remission (RR 1.9) 5

For moderate to severe symptoms (most patients):

• Proceed directly to budesonide therapy 1, 2

First-Line Pharmacologic Therapy: Budesonide

Induction Regimen

• Budesonide 9 mg once daily for 6-8 weeks is the standard induction dose 2, 6
• Evaluate symptomatic response at 4-8 weeks to determine need for therapy modification 6
• After achieving remission, taper budesonide over 1-2 weeks rather than abruptly discontinuing 6

Common Pitfall

Do not use conventional corticosteroids (prednisolone/prednisone) as first-line therapy—while effective, they have significantly more adverse effects than budesonide and should be reserved for refractory cases 1, 2

Alternative First-Line Options (When Budesonide Not Feasible)

Mesalamine is the preferred alternative with moderate quality evidence:

• Dose: 3 g daily orally 7
• Less effective than budesonide but reasonable alternative 2, 7

Bismuth subsalicylate can be considered as second-line alternative:

• Low quality evidence supporting clinical response 2, 7
• Significant pill burden limits tolerability 7

Cholestyramine may be effective for patients unresponsive to or intolerant of aminosalicylates:

• Particularly useful if bile salt malabsorption is suspected 4

Maintenance Therapy (For Relapsing Disease)

Budesonide maintenance is strongly recommended only for patients who experience symptom recurrence after discontinuation of induction therapy—up to one-third of patients may not require maintenance therapy 1, 2

Maintenance Dosing Strategy

• Start with budesonide 6 mg daily 1, 6
• Taper to the lowest effective dose (commonly 3 mg daily or 3 mg alternating with 6 mg daily) 1, 6
• This regimen reduces risk of clinical relapse by 66% (RR 0.34,95% CI 0.19-0.6) 1, 2
• Effectively maintains histological response and quality of life 1

Duration and Monitoring

• Continue maintenance therapy for 6-12 months before attempting discontinuation 1, 2, 6
• Critical caveat: Although budesonide has low systemic bioavailability, prolonged use may predispose to bone loss 1, 6
• Implement osteoporosis prevention and screening in patients requiring maintenance therapy beyond 6 months 1, 2, 6

Refractory Disease Management

For patients not responding to budesonide:

• Re-evaluate for other causes of diarrhea, particularly celiac disease, bacterial overgrowth, or chronic infection 2, 4
• Consider whether symptoms represent functional bowel disorders or post-inflammatory symptoms rather than active microscopic colitis 2
• Very limited case series evidence suggests immunosuppressants (azathioprine) or anti-TNF agents may benefit corticosteroid-refractory patients 1, 5
• Surgical intervention (fecal stream diversion or subtotal colectomy) remains an option of last resort 4

Treatments NOT Recommended

Avoid these interventions based on evidence:

• Probiotics (conditional recommendation, low quality evidence) 2
• Boswellia serrata (conditional recommendation, low quality evidence) 2
• Combination therapy with cholestyramine and mesalamine (not superior to mesalamine alone) 2

Clinical Context

The introduction of budesonide has revolutionized treatment, with studies showing that 33% of patients required two or more medications before widespread budesonide use compared to only 15% afterward (p = 0.001) 5. Despite being a chronic condition, microscopic colitis is predominantly benign and self-limiting in many patients 5, 3.