4-Hydroxymephenytoin is the major metabolite of mephenytoin in the human body catalyzed by CYP2C19, an anti-epileptic drug and a typical substrate of CYP2C19 [1]. 4-Hydroxymephenytoin is often used to develop ultra-performance liquid chromatography (UPLC) tandem mass spectrometry methods to evaluate CYP probe drugs and their related metabolites in human urine or plasma samples [2-3].
References:
[1]. Tanaka M, Kato K, Sudo KI, et al. Simple and selective assay of 4-hydroxymephenytoin in human urine using solid-phase extraction and high-performance liquid chromatography with electrochemical detection and its preliminary application to phenotyping test. Journal of Chromatography B: Biomedical Sciences and Applications. 1996 Feb 9; 676(1): 87-94.
[2]. Stewart NA, Buch SC, Conrads TP, et al. A UPLC-MS/MS assay of the “Pittsburgh cocktail”: six CYP probe-drug/metabolites from human plasma and urine using stable isotope dilution. Analyst. 2011; 136(3): 605-612.
[3]. Zhou HH. CYP2C19 genotype determines enzyme activity and inducibility of S-mephenytoin hydroxylase. Clinica chimica acta. 2001 Nov 1; 313(1-2): 203-208.
4-Hydroxymephenytoin是mephenytoin在人体内经CYP2C19催化的主要代谢产物，mephenytoin是一种抗癫痫药物，也是CYP2C19的典型底物 [1]。4-Hydroxymephenytoin常用于开发超高效液相色谱（UPLC）串联质谱方法，以评估人尿液或血浆样本中的CYP探针药物及其相关代谢物 [2-3]。