一、口服抗凝剂与四环素:抗凝剂与维生素K药理作用相互拮抗。肠道中的共栖微生物能产生维生素K,因而口服四环素后的肠道灭菌作用,可增强抗凝药的作用,故伍用时应减少抗凝剂用量。口服抗凝剂与其它广谱抗生素合用,均可使抗凝作用增强。二、双香豆素类与甲氰咪胍:甲氰咪胍抑制肝脏代谢,从而导致双香豆素类在体内浓度增加引起出血。 First, oral anticoagulants and tetracycline: anticoagulant and vitamin K pharmacological antagonism. The commensal microorganisms in the intestine can produce vitamin K, so the intestinal sterilization after oral administration of tetracycline, can enhance the role of anticoagulants, it should be used when the amount of anticoagulants should be reduced. Oral anticoagulants and other broad-spectrum antibiotics, can make anticoagulant effect. Second, dicoumarins and cimetidine: Cimetidine inhibits liver metabolism, resulting in increased concentrations of dicoumarins in the body caused by bleeding.