1例55岁男性二尖瓣重度关闭不全患者行二尖瓣机械瓣置换术后长期服用华法林抗凝治疗，国际标准化比值（INR）维持在2.00~3.00。因口腔溃疡，患者用自购的蒲公英晒干后泡服代茶饮。15 d后，患者轻微活动即出现胸闷、气短、心悸、乏力，继而出现恶心、呕吐，双下肢轻度水肿，夜间端坐呼吸，右下肢瘀斑，大便呈黑色；实验室检查示血红蛋白52 g/L，红细胞计数2.05×10n 12/L。考虑为消化道出血，可能与服用华法林期间饮用蒲公英水有关。停用华法林，停饮蒲公英水。给予滤白悬浮红细胞2 U静脉滴注、1次/d，共2次，埃索美拉唑80 mg静脉滴注、2次/d，维生素Kn 1 10 mg肌内注射和20 mg口服各1次等对症治疗。2 d后患者INR 1.58，血红蛋白84 g/L，红细胞计数2.33×10n 12/L；5 d后INR为1.63，血红蛋白104 g/L，红细胞计数3.92×10n 12/L。n “,”A 55-year-old male patient with severe mitral valve insufficiency received long-time warfarin anticoagulation therapy after mechanical mitral valve replacement and the international standard ratio (INR) was 2.00-3.00. Because of oral ulcers, he took the water soaked with dandelion (n Taraxacum mongolicum Hand-Mass.), which was self-purchased and sun-dried, for daily drinking. Fifteen days later, the patient developed chest tightness, shortness of breath, palpitation, and fatigue, followed by nausea, vomiting, mild edema of the lower limbs, orthopnea at night, ecchymosis on the right lower limb, and black stool successively. Laboratory tests showed hemoglobin 52 g/L, red blood cell count 2.05×10n 12/L. Gastrointestinal bleeding was considered, which might be related to the water soaked with dandelion drunk during warfarin therapy. Warfarin and water soaked with dandelion were stopped. The patient received symptomatic treatments including IV infusions of leukocyte-depleted red blood cell suspension 2 units (2 times in total) and esomeprazole 80 mg (twice daily), an intramuscular injection of vitamin Kn 1 10 mg, and oral vitamin Kn 1 20 mg. Two days later, the patient′s INR was 1.58, hemoglobin was 84 g/L, and red blood cell count was 2.33×10n 12/L. Five days later, his INR was 1.63, hemoglobin was 104 g/L, and red blood cell count was 3.92×10n 12/L.n