High impact information on Hydroxyomeprazole

• The 2-hour postdose plasma concentration ratio of omeprazole to 5'-hydroxyomeprazole was used as a measure of CYP2C19 activity [1].
• AUC ratios for hydroxyomeprazole/omeprazole increased 2.2-fold (1.7, 2.7) on day 7 compared with values on day 1 [2].
• Omeprazole, omeprazole sulfone, and hydroxyomeprazole pharmacokinetics were calculated from the respective plasma concentration-time curves [3].
• The ratio between the plasma concentrations of omeprazole and hydroxyomeprazole (metabolic ratio; MR) was determined by HPLC in a blood sample drawn 3 h after drug intake [4].
• In contrast, the formation kinetics of hydroxysulphone from hydroxyomeprazole were linear [5].

Anatomical context of Hydroxyomeprazole

• Preliminary studies of the formation of omeprazole sulphone and hydroxyomeprazole showed that the formation kinetics in human liver microsomes were biphasic for both metabolites, suggesting that at least two different cytochrome P450 isoforms are involved in their formation [6].

Associations of Hydroxyomeprazole with other chemical compounds

• The 8-hour urinary mephenytoin S/R ratio after ingestion of 100 mg mephenytoin and the plasma concentration ratio of omeprazole/hydroxyomeprazole at 3 hours after ingestion of 20 mg omeprazole were used as measures of CYP2C19 activity [7].

Gene context of Hydroxyomeprazole

• Logarithms of metabolic indexes of omeprazole/hydroxyomeprazole for CYP2C19 and omeprazole/omeprazole sulfone for CYP3A4 had trimodal distributions [8].
• Inhibition studies with isoform selective inhibitors also indicated a dominant role of S-mephenytoin hydroxylase with some CYP3A contribution in the formation of hydroxyomeprazole [9].

Analytical, diagnostic and therapeutic context of Hydroxyomeprazole

• Determination of omeprazole, hydroxyomeprazole and omeprazole sulfone using automated solid phase extraction and micellar electrokinetic capillary chromatography [10].
• A method has been developed and validated for the quantitation of midazolam, alphahydroxy-midazolam, omeprazole, and hydroxyomeprazole from one 250 microL sample of human plasma using high performance liquid chromatography coupled to tandem mass spectrometry [11].

References