Can tranexamic acid (TXA) stop a lower gastrointestinal (GI) bleed?

Tranexamic Acid for Lower GI Bleeding

Tranexamic acid (TXA) is not recommended for the treatment of lower gastrointestinal bleeding as it has not been shown to reduce blood loss, decrease transfusion requirements, or improve clinical outcomes in patients with lower GI hemorrhage. 1, 2, 3

Evidence Against TXA for Lower GI Bleeding

The most recent evidence specifically examining TXA for lower GI bleeding shows:

• A 2024 double-blind prospective randomized controlled trial found no significant effect of intravenous TXA on blood transfusion requirements in patients with lower GI bleeding 3
• A 2018 randomized placebo-controlled clinical trial showed no difference in hemoglobin drop (11 g/L for TXA vs 13 g/L for placebo), transfusion rates, or intervention rates for bleeding when using TXA for lower GI hemorrhage 4
• The British Society of Gastroenterology guidelines do not recommend TXA for acute lower GI bleeding, suggesting its use be confined to clinical trials 1
• Current clinical guidelines (2025) explicitly state that TXA does not reduce rebleeding rates and has not demonstrated mortality benefit in GI bleeding 2

Management Algorithm for Lower GI Bleeding

Instead of TXA, the following approach is recommended for lower GI bleeding:

1. Initial Assessment and Resuscitation:

   • Assess hemodynamic status and initiate fluid resuscitation as needed
   • Use a restrictive transfusion threshold of 70 g/L (aiming for 70-100 g/L) 1
   • Consider a higher threshold for patients with cardiovascular disease

2. Diagnostic Approach:

   • For hemodynamically unstable patients or those with shock index >1, perform CT angiography to localize bleeding 1
   • For stable patients, perform colonoscopy within 24 hours after adequate bowel preparation 5
   • Consider upper endoscopy if brisk rectal bleeding with hemodynamic instability is present (10-15% of apparent lower GI bleeds are actually upper GI sources) 1

3. Therapeutic Interventions:

   • Provide endoscopic hemostasis for high-risk stigmata (active bleeding, non-bleeding visible vessel, adherent clot) 5
   • Consider interventional radiology for ongoing bleeding not responding to endoscopic therapy 1
   • Surgical intervention should be reserved for uncontrolled hemorrhage after failed endoscopic and radiological approaches 5

4. Medication Management:

   • Interrupt direct oral anticoagulants at presentation 1
   • For life-threatening hemorrhage on DOACs, consider specific reversal agents like idarucizumab (for dabigatran) or andexanet alfa (for factor Xa inhibitors) 1
   • Restart anticoagulation approximately 7 days after hemorrhage if the bleeding source has been controlled 1

Important Caveats and Pitfalls

• Avoid using TXA for lower GI bleeding outside of clinical trials, as it carries thromboembolic risk (relative risk 1.85) without proven benefit 2
• Do not assume all rectal bleeding is from a lower GI source; up to 15% of patients with hematochezia have an upper GI source 1
• Avoid NSAIDs in patients with a history of lower GI bleeding, particularly if secondary to diverticulosis or angioectasia 5
• For patients on aspirin for secondary cardiovascular prophylaxis, do not permanently discontinue therapy after lower GI bleeding 5

While a case report has described successful use of TXA in a Jehovah's Witness patient with GI bleeding who refused blood products 6, this represents an exceptional circumstance and does not override the evidence from randomized controlled trials showing lack of benefit in the general population with lower GI bleeding.