The prothrombin time is super high after high-dose chemotherapy for bone marrow transplantation, and the dose of chemotherapeutic drugs should be adjusted if necessary, or coagulation factors should be supplemented for alternative treatment. 1. High-dose chemotherapy is relatively necessary for bone marrow transplantation, so supplementation of coagulation factors, such as transfusion of cold precipitates, vitamin K, frozen plasma, etc., should be carried out first. 2. However, if the improvement is not obvious after supplementation of coagulation factors, or accompanied by severe bleeding tendency or organ bleeding, chemotherapy can be stopped or the dose of chemotherapeutic drugs can be reduced as appropriate. Normal prothrombin time is 16~18 seconds, if it exceeds the normal value by more than 3 seconds, it is considered as overtime. Ultra-high prothrombin time is seen in plasma fibrinogen hypoplasia or structural abnormality. The application of high-dose chemotherapeutic drugs, such as leucovorin, in bone marrow transplantation will adversely affect the normal hematopoietic function of the human body and destroy the normal coagulation function of the coagulation system. If the prothrombin time of high-dose chemotherapy for bone marrow transplantation is super high, it is recommended that standardized treatment be carried out as early as possible under the guidance of a physician in order to reduce the adverse effects of the disease. All of the above medications should be used under the guidance of a doctor, avoid self-medication.