Tranexamic Acid for Lower GI Bleeding

Primary Evidence Against Routine Use

The British Society of Gastroenterology recommends that tranexamic acid use in acute lower GI bleeding should be confined to clinical trials pending definitive evidence, based on the highest quality evidence showing no mortality benefit and increased risk of venous thromboembolism 1
Historic upper GI bleeding trials that showed mortality benefit were conducted before modern endoscopic therapy and high-dose acid suppression, making them non-generalizable to current practice 1
Pooled analyses showing mortality benefit lost statistical significance when limited to trials at low risk of bias 1
Insufficient data on thromboembolic risk in the GI bleeding population at that time 1

The American College of Gastroenterology does not have specific guidelines, however, the British Society of Gastroenterology guidelines state that tranexamic acid has no significant effect on transfusion needs in lower GI bleeding 1

For Hereditary Hemorrhagic Telangiectasia (HHT) with chronic GI bleeding, the American Society of Hematology recommends tranexamic acid for mild GI bleeding in HHT patients, with dosing starting at 500 mg twice daily, gradually increasing to 1000 mg four times daily or 1500 mg three times daily 2, 3
Contraindications for tranexamic acid in HHT patients include recent thrombosis, and relative contraindications include atrial fibrillation or known thrombophilia 2

For acute lower GI bleeding, the British Society of Gastroenterology recommends not administering tranexamic acid routinely, and instead focusing on resuscitation, endoscopic identification and therapy, and ensuring access to interventional radiology if endoscopy fails 1
For chronic lower GI bleeding in HHT only, the American Society of Hematology recommends grading bleeding severity and considering oral tranexamic acid for mild bleeding, with screening for thrombosis contraindications before initiating 2, 3

The British Society of Gastroenterology and the American Association for the Study of Liver Diseases recommend not extrapolating trauma or surgical bleeding data to GI bleeding, and not assuming "antifibrinolytic = less bleeding" universally, as GI bleeding mechanisms involve vascular injury and portal pressure, not just fibrinolysis 1, 4
The American Association for the Study of Liver Diseases also recommends not ignoring the increased VTE risk, particularly in patients with liver disease 4

The European Association for the Study of the Liver recommends that tranexamic acid use in patients with renal impairment should be avoided due to the risk of neurotoxicity and ocular toxicity, as the drug is 90% renally excreted and accumulates in renal dysfunction 5
The American Society of Hematology suggests that tranexamic acid may be considered only in Hereditary Hemorrhagic Telangiectasia (HHT) patients with chronic GI bleeding, starting at 500 mg twice daily and titrating to 1000 mg four times daily 6

The British Society of Gastroenterology recommends a restrictive transfusion strategy, transfusing only when hemoglobin is low, with a target of 7-9 g/dL 5