1.When blood clots, vomiting blood, fresh blood or tarry stools, bleeding gums, blood in sputum, purpura, chest pain, pelvic pain, headache, dizziness, prolonged bleeding after minor trauma or any symptoms of hepatitis (darkening of urine, itching of skin, jaundice, lightening of stool color, clay color) occur, the drug should be stopped immediately and contacted with the doctor. 2.Take the medication at the same time every day, preferably at night, so that the dosage of the day can be adjusted. The dosage and brand of the medication should not be changed without the doctor’s permission, and if you miss a dose you need to make it up as soon as possible, but you should not increase the dosage in order to make up for it. 3. Do not take other medications, including aspirin, antibiotics and cold medications, without your doctor’s permission during the medication period. These drugs can interfere with the action of Warfarin and cause health hazards. 4.Influenza vaccine makes the effect of anticoagulation increase, check for bleeding within one month of vaccination. 5.Fever, climate fever, malnutrition and diarrhea can prolong the clotting time causing bleeding. 6.Keep a balanced, relatively regular diet and good eating habits, and keep in mind to eat less high-fat diet and foods rich in vitamin K such as: cabbage, cauliflower, asparagus, lettuce green radish, fish, liver, etc. 7, avoid alcohol abuse. Drinking alcohol can accelerate the metabolism of Warfarin and shorten the bleeding time. Avoid trauma and bleeding as much as possible. 8.Use a soft toothbrush, use an electric razor to shave, wear gloves when cultivating flowers and plants, and check with your doctor before participating in sports to see if the physical condition is not suitable for sports. 9, quit smoking or smoke as little as possible, smoking can speed up the metabolism of the drug need to adjust the dose. 10, Warfarin can cause miscarriage, stillbirth, fetal malformation, if the patient is pregnant or preparing to become pregnant please tell your doctor. 11, regular testing of blood coagulation series, testing interval of no more than 4 weeks, senior patients should pay more attention, monitoring any changes at any time, they are taking Warfarin, please tell your doctor when you visit.