Action: Coumarin-based anticoagulant for patients who need long-term continuous anticoagulation. Precautions: 1. Reactions such as nausea, vomiting, diarrhea, pruritic rash, allergic reaction and skin necrosis are rarely seen. 2. Foods that reduce the anticoagulant effect of Warfarin: foods rich in vitamin K, such as spinach, cabbage, carrots, tomatoes, pork liver, potatoes, egg yolk, soybean oil, cod liver oil, seaweed, tomato paste, pumpkin, fish eggs, cream, butter, meat, milk, fruits, nuts, broccoli, cauliflower, barley, etc. Drugs that enhance the anticoagulant effect of warfarin: salicylates, broad-spectrum antibiotics, sulfonamides, clofibrate, aspirin, pansentin, botrytisine, quinidine, angelica, etc. Drugs that reduce the anticoagulant effect of Warfarin: rifampin, barbiturates, streptomycin, metronidazole, cimetidine, ambrisentin, vitamin K, contraceptives and hormones, ginseng, tea, etc. The efficacy and toxicity of Warfarin in combination with chloral hydrate are increased and should be reduced.