Abstract Body (Do not enter title and authors here): Background: Apixaban and rivaroxaban are common agents used for anticoagulation to treat and prevent blood clots and to prevent stroke in people with atrial fibrillation.

Research question: As anticoagulants, there is a risk of bleeding occurring. The question is, which of these two medications has a higher risk of bleeding from various organ systems.

Goals: Using the FAERS database to calculate the reporting odds ratio (ROR) for the risk of ocular, cerebral, gastrointestinal, rectal, and renal hemorrhage in addition to epistaxis and hemoptysis of these medications.

Methods: We manually extracted data from the FAERS database owned by the FDA on hemorrhagic events related to Apixaban and Rivaroxaban from January 2012 to March 2024. We calculated the reported odds ratio for both drugs to compare their respective hemorrhagic outcomes.

Results: The total AE reported for apixaban and rivaroxaban from 2012 to March 2024 was 87490 and 88026, respectively. Rivaroxaban has an increased risk for cerebral (ROR 1.73, 95% CI 1.60 to 1.86), gastrointestinal (ROR 5.91, 95% CI 5.61 to 6.22), rectal (ROR 4.64, 95% CI 4.21 to 5.12), renal (ROR 3.83, 95% CI 2.87 to 5.11), epistaxis (ROR 2.06, 95% CI 1.93 to 2.20) and hemoptysis (ROR 3.20, 95% CI 2.80 to 3.66) compared to apixaban with a significant p-value. There was no statistical significance in reported cases of ocular hemorrhage in apixaban versus rivaroxaban.

Conclusion: Apixaban and rivaroxaban are common medications used in the treatment of people with atrial fibrillation to reduce the risk of clots and stroke. The FAERs database compared the risk of ocular, cerebral, gastrointestinal, rectal, and renal hemorrhage and epistaxis and hemoptysis of these medications. There was no statistical significance in reported cases of ocular hemorrhage in apixaban versus rivaroxaban. Rivaroxaban overall has a significantly higher risk of bleeding in multiple organ systems, especially cerebral, gastrointestinal, rectal, and renal hemorrhage, as well as epistaxis and hemoptysis. Apixaban would be a better option for people at risk for or with a history of these complications.