英妥英钠及其与卡马西平联用致中毒的血浓度观察

OBSERVATION ON SERUM DRUG CONCENTRATION POISONEDBYPHENYTOINANDPNENYTOIN COMBINED WITHCARBAMAZEPINE

报告２５例单用苯妥英钠（ＰＨＴ）和１２例ＰＨＴ与卡马西平（ＣＢＺ）联用引起中毒的癫痫患者的血药浓度。结果：在两组口服ＰＨＴ剂量相近（Ｐ＞Ｏ．０５）时，单药组ＰＨＴ平均血浓度为４８．４６±１１．４９μｇ／ｍｌ，联用组ＰＨＴ平均血浓度为２４．８６土７．３２μｇ／ｍｌ，口服ＣＢＺ平均剂量Ｏ．４３ｇ／ｄ，平均血药浓度为２６６±１．０３μｇ／ｍｌ。表明单用ＰＨＴ致中毒时平均血浓度约为联合用药时ＰＨＴ血浓度的２倍。揭示ＣＢＺ可能影响ＰＨＴ的药动学，从而降低了ＰＨＴ的血浓度。联合用药组ＰＨＴ的中毒血浓度明显低于单药组，揭示ＣＢＺ可使ＰＨＴ的毒性加强，即使在有效治疗血药浓度内也可诱发中毒症状。认为两药联用时，不宜用ＰＨＴ的血浓度作为调整剂量的参考指标。

he serum phenytoin concentration was reported in epileptic patients who were poisonedwithphenytoin(PHT) monotherapy in 25 cases and with phenytoin combined with carbamazepine (CBZ)in l2 cases. When the doses of PHT given orallyintwo groups were similar (P>O.O5),themean serum concentration of PHT was48.46±11.49μg/ml( in the monotherapeutic group)and 24.86±1.03μg/ml in thd combination group.It indicated that the mean serum concentrtion ofthe monotkerapeuticgroup poisoned by PHT was about two times that of the combination group.The mean oral dose of CBZ per day was 2.66±1.03μg/ml.It suggested that CBZ might influencethe pharmacodynamics of PHT ,thus decreasing the PHTserum concentration. In the combinationgroup ,the poisoning concentration of PHT was obviously lower than that in the monotherapeuticgroup。 It suggested that CBZ could strengthen the toxicity of PHT. Even though the concerntra-tion of PHT was within effective range ,it could result in poisoning symptoms.lt was thought thatwhen two drugs were used concomittantly ,the serum concentration of PHT could not be used as areference index for regulating the dosage.