Many primary care doctors or junior doctors always feel overwhelmed by the application of warfarin, especially the dose selection and adjustment at the start of treatment. According to some experts’ advice and personal experience, I share with the children: 1, the application of warfarin must pay attention to the indications, that is, the need for the application of the patient to apply, before the application must explain the need for the application and the possible risks (mainly bleeding risk). Patients must give their informed consent. 2, warfarin is currently mainly imported 3mg/tablet, and domestic 5mg/tablet two, it is recommended to apply the imported dosage form. Imported drug dose is more accurate, each tablet dose is smaller, more convenient to use. Imported drugs are generally better quality than domestic drugs, you know, and patients to explain clearly, although a little more expensive but worth it. 3, acute anticoagulation treatment application warfarin, should be given in the oral warfarin treatment at the same time heparin treatment for 4 days, can choose subcutaneous injection of low molecular heparin. 4, the choice of warfarin starting dose, although the U.S. guidelines recommend 4-5mg in fact, domestic experts still recommend the Chinese initial dose of 3mg, older than 75 years and higher bleeding risk patients 2mg to start, once daily oral. 5, INR needs to be monitored. If there is no condition to monitor INR, please choose warfarin treatment carefully. INR is routinely tested before dosing, and must be tested once 2-3 days after dosing, and warfarin can be adjusted according to the test results. If INR is not ideal, INR should be tested once every 2-3 days during dose adjustment. warfarin adjustment is 0.5mg-1.0mg/time. After the INR reaches the ideal value, it can be changed to once a week, and if the indicators are stable for 3-4 consecutive weeks, it can be changed to once a month. 6.The target range of INR is 2.0-3.0, and most doctors recommend controlling it at 1.5-2.5. 7.Tell the patient to take the medication at the same time every day, and 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, and if the time for the next dose is close, you can take it without making up for it, and just take the next dose directly without making up for it. 8, suffering from other diseases, or taking other drugs should consult the doctor whether the need to adjust the warfarin dose, certain drugs can not be taken with warfarin, patients should be reminded to pay special attention. 9, life should quit smoking and alcohol, prevent accidental injury, maintain a balanced, relatively fixed diet and eating habits, avoid excessive changes in the intake of vitamin K. 10.Mild bleeding from oral anticoagulants is more common than aspirin. Common bleeding is oral (gum) bleeding, nasal bleeding, subcutaneous bruising or hematoma, subconjunctival bleeding, microscopic or naked eye hematuria, respiratory bleeding, increased menstruation or black stool, etc. The majority of bleeding is controlled and gradually absorbed after short-term dose reduction or suspension of the drug for one to two times, and the INR level of the therapeutic dose can be restored after the bleeding is controlled, and this bleeding mostly does not affect the continuation of treatment or lead to serious consequences. Vitamin K1 is used when the patient is at risk of bleeding or when surgery or tooth extraction is required.