1. In order to adjust the drug dose, it is important to review the coagulation phase regularly. Generally, the coagulation image is checked once a week, but more frequently when you start taking the drug, and at least once every half month after stabilization, in order to confirm whether the INR (International Normalized Ratio of prothrombin time) is stable and within the target range (2,0-3,0), and based on the INR result, your doctor can adjust the drug dose for you and and determine whether you are at risk of bleeding. 2. When blood clots, vomiting of blood, fresh blood or tarry stools, bleeding gums, blood in sputum, skin petechiae, chest pain, pelvic pain, headache, dizziness, prolonged bleeding after minor trauma or symptoms of hepatitis (dark urine, yellow stained skin, itching, white stools) occur, discontinue the drug immediately and contact your doctor or seek medical attention. 3.Take the medicine at the same time every day, should not change the dose and brand without the doctor’s permission, if you miss one dose, you need to make up for it as soon as possible, if the time of the next dose is close, you can take it without making up for it, just take the next dose directly at that time, no need to make up for it. 4.Don’t take other drugs, including aspirin and cold medicine, without doctor’s permission during the medication period, as these drugs can interfere with the effect of warfarin and cause health hazards. 5.Influenza vaccine increases the anticoagulant effect, and it is necessary to check for bleeding within 1 month of vaccination. 6.Fever, malnutrition and diarrhea can prolong the clotting time causing bleeding. 7, avoid alcohol, alcohol consumption can increase the metabolism of warfarin and shorten the clotting time. 8.Avoid trauma and bleeding as much as possible, use a soft toothbrush, shave with an electric razor, wear gloves when cultivating flowers and plants, move appropriately and avoid strenuous exercise. 9, quit smoking or try to smoke less, smoking can speed up the metabolism of warfarin and the need to adjust the drug. 10, warfarin can cause miscarriage, stillbirth, fetal malformation. If the patient is pregnant or preparing to become pregnant please tell your doctor to give you advice. 11.Maintain a balanced, relatively regular diet and eating habits to avoid excessive changes in vitamin K intake. Some foods contain more vitamin K, such as: fish, liver, broccoli, kale, cabbage, cauliflower, lettuce, asparagus, green radish and green leafy vegetables such as spinach and lettuce. 12.When you go to the hospital, tell your doctor that you are taking oral warfarin, carry your medical records and recent test results with you, and indicate that you are receiving warfarin treatment.