What is warfarin Warfarin is a vitamin K antagonist that is the most commonly used drug in vascular surgery to prevent recurrence of deep vein thrombosis. It is an inexpensive and effective anticoagulant, but the dietary combination of warfarin is very careful and deserves the attention of the patients. International standardized prothrombin time (INR) monitoring 1, the initial dose of warfarin is 2.5mg (1 tablet), after 3 days of continuous use, the INR index of the four coagulation items will be tested on the 4th day. 2. Adjust the INR value between 2.0-3.0 by adjusting the warfarin dose, and control the INR between 1.70-2.50 for safety in elderly patients. Doses below 2.0 should be increased and above 3.0 should be reduced. The dosage should not be increased or decreased by more than 1/4 tablet per day. If INR>5.0, stop using warfarin for one day and then reduce 1/4 tablet to continue oral intake. 3, after reaching the target dose need to be tested every other day, two consecutive tests INR indicators between 2.0-3.0, warfarin dose can be stabilized, continuous use. Follow the doctor’s instructions to adjust to once a week or once a month testing. Precautions for combined medication 1.Enhance the efficacy of warfarin: Fenbid, deprenyl tablets and other NSAIDs and analgesics, Antomin, broad-spectrum antibiotics, sulfonamides, allopurinol, quinidine, can act synergistically to enhance the efficacy of warfarin and easily cause bleeding. 2, weaken the efficacy of warfarin: western ginseng, vitamin C, corticosteroids, phenytoin sodium, androstenedione, hypnotics, digitalis, epinephrine, atropine, acetylcholine, ashwagandha, rifampin, estrogen can reduce the efficacy of warfarin and cause thrombosis. 3. When the above drugs are combined with warfarin, the INR should be monitored and the warfarin dosage should be adjusted promptly. Dietary considerations Vitamin K-rich foods include acid cheese, pork liver, egg yolk, barley, beans, carrots, tomatoes, safflower oil, soybean oil, cod liver oil, seaweed, broccoli, green pepper, garlic, ginger, cauliflower, green leafy vegetables (spinach, rape, alfalfa, lettuce, cabbage) and pears, apples, peaches, oranges, etc. Green leafy vegetables are rich in vitamin K. The vitamin K content per 100 grams of vegetables is 380 mg of spinach, 315 mg of dark green leafy lettuce, and 145 mg of cabbage. Although foods rich in vitamin K or foods that interfere with vitamin K synthesis can affect the efficacy of warfarin, this does not mean that patients need to completely avoid these foods, but rather need to maintain a relatively balanced diet, taking care to reduce the intake of vitamin K-rich foods (the daily intake of vitamin K for adults is 65-80 micrograms), not to mention the need to overly restrict the intake of vegetables with low vitamin K Intake of vegetables with low vitamin K content (for example, onions have fibrinolytic activity and should not exceed 60 grams in 1 day). After all, vegetables and fruits can provide other nutrients that are necessary for the health of the whole organism. Therefore, in order to maintain the stability of the anticoagulant efficacy of warfarin, it is necessary for patients to maintain a relatively balanced dietary structure and not to arbitrarily switch the type and quantity of vegetables while taking the drug. In fact, in addition to taking care to avoid excessive intake of vitamin K-rich foods, it is also important to pay attention to the approach in life care. When some people abuse antimicrobial agents and diarrhea, disrupting the balance of intestinal flora also reduces the beneficial intestinal flora that produce vitamin K and coagulation factors, resulting in prolonged clotting time and easily causing vitamin K deficiency, which can also easily lead to bleeding if warfarin is used at this time. Other Precautions 1. If a patient has unexplained heavy bleeding from the gums, unprovoked nosebleeds that do not stop, subcutaneous bruises and bruises without trauma, black stools, vomiting blood (or vomiting coffee-colored liquid), or blood in the urine, please seek immediate medical attention. The doctor will decide whether warfarin needs to be reduced or stopped. 2, please pay attention to avoid strenuous exercise and mood swings, elderly patients pay attention to blood pressure control, avoid trauma and bump. 3.When invasive examinations or treatments such as angiography, deep venipuncture or even surgery are needed for other diseases, patients and their families should inform the treating physician in advance about the warfarin medication, and if necessary, stop the medication until the PT is normal or use vitamin K antagonism.