Valproic Acid與Carbapenems類抗生素之藥物交互作用

Drug Interaction between Valproic acid and Carbapenems

Valproic acid （VPA）為一常用於全身僵直陣攣型發作與局部型發作的抗癲癇藥物，會與多種藥物產生藥物交互作用而影響臨床治療效果；carbapenems 類抗生素與VPA 併用可能導致VPA 藥物血中濃度的快速下降，近年來有許多案例也被廣泛的探討。引起此藥物交互作用的可能機制有：減少VPA 在腸道的吸收、干擾VPA 的腸肝循環、加速VPA 的葡萄糖醛酸反應與排除、抑制VPA 由紅血球細胞內層傳送到外層。臨床上兩類藥品併用時應多加注意，尤其在老年族群或有中樞神經疾病的患者，若因病情需要須併用時，建議增加 VPA 的血中濃度監測次數並嚴密觀察，以減少因VPA 濃度下降引起癲癇再發或惡化的情形發生。

Valproic acid (VPA) is a widely used anticonvulsant for the treatment of generalized tonic-clonic and partial seizures. It is well known that drug interactions between VPA and many other drugs would affect the therapeutic effect of VPA. Concomitant administration of carbapenems and VPA may lead to rapid decline in serum VPA concentrations, and many cases have been discussed and published recently. The followings are the possible mechanisms related this drug interaction: decrease the absorption of VPA in the intestine, interruption the enterohepatic circulation by VPA, increase in the glucuronidation reaction for VPA excretion, and inhibition of VPA efflux from erythrocytes. Co-administration of carbapenem antibiotics and VPA should be careful, especially in the elderly and patients with central nervous system disorders. If the concomitant use of both drugs is inevitable, very close monitoring of serum VPA concentration and clinical observations are necessary to prevent seizures and clinical deterioration.