The most common cause of gastrointestinal bleeding in cardiac patients may be related to oral antiplatelet or anticoagulant drugs. Many cardiac patients need oral antiplatelet drugs, such as coronary heart disease patients need oral aspirin, clopidogrel and other drugs, antiplatelet drugs on the gastrointestinal mucosa will cause damage, while inhibiting the aggregation of platelets, which can easily lead to bleeding in the digestive tract. Some cardiac patients need oral anticoagulant therapy, for example, some patients may have atrial fibrillation and need oral warfarin or rifaxaban. Anticoagulant drugs can lead to prolonged coagulation, which can also increase the risk of gastrointestinal bleeding. When taking oral antiplatelet and anticoagulant drugs, cardiac patients should pay attention to protect the mucosa of the gastrointestinal tract to prevent the occurrence of gastrointestinal bleeding, and take the appropriate dosage orally under the guidance of a physician, as well as the scientific prevention of gastrointestinal bleeding.