1例胺碘酮致华法林抗凝作用增强病例分析

目的 探讨临床药师在华法林抗凝治疗时联用胺碘酮引起国际标准化值(INR)异常升高的处理方法及药学监护。 方法 通过对照华法林与其他药物相互作用的情况,确定引起INR值异常波动的药物,及时调整华法林剂量,加强凝血功能的监测,并从华法林与胺碘酮的作用机制、相互作用、两药联用后抗凝作用与两药的剂量、浓度相关性等方面阐述胺碘酮对华法林抗凝作用的影响。 结果 INR异常波动为华法林与胺碘酮联用所致,两药联用可增强华法林的抗凝作用,增加出血风险,通过停用华法林3 d,INR恢复到目标值范围,继续给予华法林抗凝治疗,患者情况控制平稳,顺利出院。 结论 临床药师通过对患者有效的药学监护,可协助临床及时发现药物治疗相关问题。在使用与华法林有相互作用的药物时要考虑其对抗凝治疗的影响,一方面要充分了解药物合用时的药理学及药动学变化,另一方面要加强监测,以便及时调整用药方案,提高临床用药的安全性和合理性,更好地为患者提供药学服务。

A case study: amiodarone enhanced warfarin anticoagulation effects for post heart value replacement

Objective To explore the role of clinical pharmacists in analyzing and dealing with abnormal INR value fluctuations caused by the drug interaction of warfarin and amiodarone in a post heart valve replacement patient. Methods By comparing interactions between warfarin and other drugs, we investigated the drugs the patient was using, found the cause of unusual INR value fluctuations, and regulated warfarin dosage in time. After that, we intensified the monitoring of coagulation function and offered detailed pharmaceutical care to the patient. In addition, we studied the possible reasons for the phenomenon from the following aspects such as the drug action mechanisms of warfarin and amiodarone;the interaction mechanisms of the two drugs;the correlation of anticoagulation effects of warfarin, the dosage and concentration of combined use of these two drugs. Results The reason for unusal INR value fluctuations was identified as the drug interaction between warfarin and amiodarone. Amiodarone can enhance the anticoagulant effects of warfarin, increase the risk of bleeding. By stoping warfarin for 3 days, INR value was restored to the target range. Then we continued the anticoagulant therapy, and the condition of the patient was controlled steadily, and he was discharged smoothly. Conclusion Clinical pharmacists can help doctors find out problems related to drug therapy in time by providing effective pharmaceutical care to patients, so doctors may adjust the treatment in time. When using the drugs interacted with warfarin, we have to consider the those drug effects on anticoagulant therapy. In order to adjust regimens in time, we must understand the pharmacology and pharmacokinetics of the drugs we used at the same time;as well, we must intensify monitoring. Therefore, we can improve the safety and rationality of clinical medication, and also can provide better pharmaceutical care for patients.