What medications can trigger microscopic colitis?

Medications That Can Trigger Microscopic Colitis

Several medications are known to trigger microscopic colitis, with the most common culprits being non-steroidal anti-inflammatory drugs (NSAIDs), proton pump inhibitors (PPIs), selective serotonin reuptake inhibitors (SSRIs), and statins. 1

Key Medication Triggers

Well-Established Triggers

• NSAIDs (e.g., ibuprofen, naproxen)
• Proton Pump Inhibitors (PPIs) (e.g., omeprazole, pantoprazole)
• Selective Serotonin Reuptake Inhibitors (SSRIs) (e.g., sertraline)
• Statins (e.g., atorvastatin, simvastatin)

Other Reported Triggers

• Aspirin 2
• Beta-blockers 3
• Bisphosphonates 3

Evidence for Medication-Induced Microscopic Colitis

The British Society of Gastroenterology specifically identifies these medications as potential precipitating factors for microscopic colitis 1. Research studies have shown significant associations between these medications and microscopic colitis development:

• SSRIs have shown particularly strong associations with microscopic colitis, with one study reporting an odds ratio of 37.7 (4.7-304) for lymphocytic colitis 3
• Sertraline specifically has been identified as having a significant association with lymphocytic colitis (p < 0.0005) 3
• NSAIDs have been associated with collagenous colitis with an odds ratio of 2.9 (1.3-6.4) 3
• Statins have shown an association with lymphocytic colitis with an odds ratio of 4.6 (1.04-20) 3

Risk Factors for Medication-Induced Microscopic Colitis

Certain patient characteristics increase the risk of developing microscopic colitis when exposed to these medications:

• Female sex (particularly for collagenous colitis)
• Age ≥50 years
• Coexistent autoimmune disease
• History of nocturnal or severe watery diarrhea
• Duration of diarrhea <12 months
• Weight loss 1

Clinical Implications

When evaluating patients with chronic watery diarrhea, especially those with the risk factors listed above, clinicians should:

1. Conduct a thorough medication review, particularly focusing on NSAIDs, PPIs, SSRIs, and statins
2. Consider medication discontinuation when microscopic colitis is diagnosed or suspected
3. Perform colonoscopy with biopsies from multiple segments of the colon when microscopic colitis is suspected 1
4. Be aware that microscopic colitis can occur in younger patients (25% of cases under age 45) 1

Management Approach

When microscopic colitis is diagnosed in a patient taking potential triggering medications:

1. Discontinue the suspected triggering medication if clinically feasible
2. Consider budesonide as first-line treatment (9 mg daily for 8 weeks) 4
3. Monitor for spontaneous remission, which occurs in approximately 38% of patients 2
4. Consider alternative medications in the same class with potentially lower risk if the original medication is essential

Important Considerations

• Microscopic colitis can coexist with other conditions like bile acid diarrhea (found in 29-41% of patients with microscopic colitis) 1
• Male patients are more likely to achieve spontaneous remission (relative risk 1.9) 2
• Some studies have shown conflicting results regarding medication associations, highlighting the complex nature of this condition 5

While medication withdrawal may lead to symptom improvement, many patients will require specific treatment for microscopic colitis, with budesonide being the most effective option based on current evidence.