Generally speaking, oral drugs to prevent venous thrombosis are only needed when the body is in a hypercoagulable state, such as tumors, inflammatory infections, immune diseases, such as rheumatism, etc. Sometimes, oral drugs to prevent venous thrombosis are needed for postoperative bedridden patients, especially for patients after orthopedic joint replacement surgery. There are mainly vitamin K antagonists, that is, warfarin, non-vitamin K oral drugs, such as rivaroxaban and other new oral anticoagulants, sometimes if the above drugs can not be used, you can also use anti-platelet drugs, such as hydroclopidogrel, aspirin, etc., but in general, anti-platelet drugs are not as effective and safe as anticoagulants.