Gastrointestinal Bleeding Prophylaxis in Acute Coronary Syndrome

Primary Recommendation

• The American College of Cardiology recommends proton pump inhibitors (PPIs) as the first-line agents for gastrointestinal bleeding prophylaxis in patients with acute coronary syndrome on antiplatelet therapy, with a Class I recommendation 1, 2
• PPIs are superior to H2 receptor antagonists (H2RAs) in preventing upper GI bleeding in patients on antiplatelet therapy, with an odds ratio of 0.04 (95% CI: 0.002 to 0.21) compared to 0.43 (95% CI: 0.18 to 0.91) for H2RAs 3, 4

Evidence Supporting PPIs

• The 2025 ACC/AHA/ACEP/NAEMSP/SCAI guideline explicitly states that PPIs are recommended for patients at risk for gastrointestinal bleeding, with a Class I recommendation 1, 2
• The 2010 ACCF/ACG/AHA Expert Consensus Document notes that PPIs reduce upper GI bleeding to a greater degree than H2RAs 3, 5

Clinical Algorithm

• The American College of Cardiology recommends identifying patients requiring GI prophylaxis, including those with a history of upper GI bleeding, multiple risk factors, or on triple antithrombotic therapy 3, 5, 7
• The American Heart Association recommends selecting PPIs as the first-line agent for GI prophylaxis, with H2RAs as a second-line option only if PPIs are contraindicated or not tolerated 1, 2, 5

Important Caveats

• Famotidine is not routinely recommended as first-line therapy due to its inferior protection compared to PPIs, with a gastric acid production suppression of only 37-68% over 24 hours 5, 6
• The American College of Cardiology notes that routine use of either a PPI or an H2RA is not recommended for patients at lower risk 3