Endoscopic Evaluation for Iron Deficiency Anemia in Patients on Antithrombotic Therapy

Examinations of the gastrointestinal (GI) tract (including the stomach, small intestine, and colon) will be performed to identify the source of bleeding. These examinations may be repeated based on the treating physician's assessment. Iron supplementation (ferrous sulfate) will be administered either orally (per os) or intravenously (IV), and blood transfusions will be provided if necessary.

The investigational intervention involves a conservative treatment approach guided by a decision-making algorithm based on iron deficiency anemia values. This algorithm, developed from guidelines by the British Society of Gastroenterology and the American Gastroenterological Association, determines whether patients receive oral or IV ferrous sulfate or a blood transfusion. Laboratory parameters (hemoglobin, ferritin) will be monitored at weeks 4, 12, 38, and 64. After iron therapy, hemoglobin response will be assessed at 4 weeks, and treatment will continue for \~3 months post-normalization to ensure iron store repletion. Blood tests will be repeated every 6 months to detect recurrence.