Warfarin is wrong, take one more tablet can be temporarily observed, it is recommended to check the prothrombin time and international normalized ratio (INR) at the same time. 1. Warfarin belongs to anticoagulant drugs, can inhibit the activity of some prothrombin in the body, prolong the time of coagulation, clinically can be used for the treatment of patients after metal valve replacement, but also for the prevention of valvular heart disease embolism and other risks. 2. Warfarin is taken once a day, taking one more tablet in the course of medication may lead to prolongation of prothrombin time and risk of bleeding; if the usual prothrombin time is within the required range, you can observe the changes in the condition and test the prothrombin time at the same time, and if the value is significantly higher, you can temporarily stop the medication for once and then review it. 3. The main adverse reactions of warfarin are nausea, vomiting, diarrhea, bleeding, skin and mucous membrane bleeding is the most common, a small number of patients may have gastrointestinal bleeding or intracranial hemorrhage, it is forbidden for patients with active bleeding, allergy to the drug components, active ulcers, women during pregnancy, trauma and short-term surgery. In the process of taking warfarin, you should strictly control the dosage and method of medication, avoid taking the wrong medication to avoid the risk of bleeding, under the guidance of the doctor to make adjustments to the dose of the drug, and monitor the prothrombinogen time. Specific diagnosis and treatment need to follow the doctor’s advice.