(Disclaimer: This article is for scientific use only. Information in the following content has been processed to protect patient privacy.) Abstract: A 35-year-old young female patient was first seen in the gynecology department with vaginal bleeding, and subsequently visited the emergency department for abnormal coagulation and anemia. Based on the patient’s symptoms of vaginal bleeding, gingival bleeding, skin purpura, and abnormal coagulation function, the patient was further pursued for a history of rat poison consumption. The level of anticoagulant rat poison in blood was high. After giving fresh frozen plasma and vitamin K1 transfusion, coagulation function improved and bleeding stopped, and the patient was discharged 2 weeks later. 【Basic information】 Female, 35 years old 【Disease type】 Blood loss, moderate anemia, vaginal bleeding, rat poisoning 【Visiting hospital】 The Second Hospital of Harbin Medical University 【Visiting time】 April 2022 【Treatment plan】 Medication (saline, vitamin K1, fresh frozen plasma, red blood cell suspension) 【Treatment cycle】 Inpatient treatment for 2 weeks, review once a week after discharge 【Treatment effect After completing pelvic ultrasound, serum human chorionic gonadotropin, routine blood count, liver and kidney function, coagulation picture and other related tests, gynecological diseases were ruled out, and the patient was advised to seek emergency care because of significant abnormalities in coagulation function and anemia. When we saw the patient, we found that the patient had an anemic face, scattered purpura around the body, and self-reported symptoms of gingival bleeding and peripheral weakness in addition to vaginal bleeding for the past 10 days. Self-coagulation picture: prothrombin time 280.6 seconds, international standardized ratio 26.84. Blood count: leukocytes 19×10^9/L, erythrocytes 2.41×10^12/L, hemoglobin 67 g/L. Liver and kidney function: approximately normal. Based on previous experience, this condition is more common than hematologic diseases and anticoagulant drug intoxication. So we continued to ask the patient about his past disease history and medication history. He reported that he was usually healthy, but more than 20 days ago, he had taken 30 ml of red rat poison of unknown specific composition orally due to anger, and did not seek medical attention and treatment because he did not have any symptoms after taking it. Based on this history and the abnormal results of routine blood and coagulogram tests, we initially judged that the patient might have suffered from multiple bleeding due to poisoning with anticoagulant rat poison, and due to the long bleeding time, the patient lost too much blood and thus became anemic, a condition that required hospital admission. II. Treatment history As we highly suspected that the patient’s current bleeding might be related to rat poisoning, after admission, blood samples were collected and sent to professional institutions for testing, and it was confirmed that bromadiolone was indeed present in the patient’s body, which clarified the diagnosis of anticoagulant rat poisoning. In terms of treatment, considering that the patient had accumulated excessive blood loss, we gave the patient an emergency infusion of red blood cell suspension to rapidly correct the anemia while using saline to rehydrate the patient in appropriate amounts, and one temporary infusion of fresh frozen plasma to rapidly raise the level of coagulation factors in the body and improve the abnormal coagulation function. At the same time, the antidote vitamin K1 was administered intravenously every day. while giving the above treatment, we explained to the family the diagnosis and treatment of the patient, explaining that anticoagulant rat poisoning can lead to chronic toxic reactions, and the damage to the organism is mainly caused by abnormal coagulation function, which leads to multiple bleeding. vitamin K1 is a very effective antidote, but it takes a long time to administer, and some patients even need to be treated for 2-3 months, for which the family members should be psychologically prepared. On the second day after the transfusion of red blood cell suspension and fresh frozen plasma, the patient’s vaginal bleeding stopped at the time of room check. The patient’s coagulogram was checked urgently, and the abnormal indicators were significantly improved. 10^9/L, erythrocytes 3.07×10^12/L, hemoglobin 81g/L, normal renal and liver function, normal coagulation function, and discharge was granted. IV. Precautions The patient had a smooth treatment this time, and was relieved for this. Considering that the patient’s toxic reaction caused by taking rat poison is chronic coagulation abnormality, if the antidote vitamin K1 dose is too small, it may still bleed, but too much dose will also have certain damage to the organism, but the drug needs to be adjusted according to the results of prothrombin time, therefore, we ask the patient to continue monitoring coagulation image once a week after discharge, and vitamin K1 can be reduced for 2 consecutive normal times. During the dosing period, closely observe for gum bleeding, nasal bleeding, black stool, vomiting, hemoptysis, vaginal bleeding and skin bleeding spots or purpura. Once bleeding occurs at any site, it usually indicates that the dose of vitamin K1 needs to be increased and it is recommended that the dosage be adjusted promptly at the hospital. Advise patients and family members that the treatment period of anticoagulant rat poisoning is long, even 2-3 months, have confidence and patience that this disease can be cured and do not have psychological burden. V. Personal insight For patients with bleeding from multiple sites and combined with abnormal coagulation function, in addition to considering hematological diseases in our diagnosis, we should also pursue whether there has been a history of suicide by medication, focusing on rat poison, warfarin and other drugs affecting coagulation function, in order to avoid misdiagnosis and delay in treatment. Many patients with anticoagulant rat poisoning have basically no symptoms or only nausea and vomiting in the early stage, so people don’t care about it, so clinics often see patients who come to the clinic with bleeding as the first symptom, such as the patient in this case. Nowadays, many people who are facing high pressure of life and work often do not know how to relieve their emotions and are prone to mood swings and extreme behaviors, so it is recommended that we find appropriate ways to relieve our emotions in our lives. If you inadvertently take toxic drugs, you must seek medical attention in a timely manner.