Purpose: The inhibitory effects of omeprazole on diazepam metabolism in vitro and in vivo are compared in the rat.
Methods: 3-hydroxylation and N-demethylation of diazepam was investigated in the presence of a range of omeprazole concentrations (2-500 microM) in hepatic microsomes and hepatocytes. Zero order infusions together with matched bolus doses of omeprazole were used to achieve a range of steady state plasma concentrations (10-50mg/L) and to study the diazepam-omeprazole interaction in vivo.
Results: The 3-hydroxlation pathway was more prone to inhibition (KIs 108 +/- 30 and 28 +/- 11 microM in microsomes and hepatocytes, respectively) than the demethylation pathway (KIs of 226 +/- 76 and 59 +/- 27 microM in microsomes and hepatocytes, respectively). In both in vitro systems, the mechanism of inhibition was competitive with Km/KI ratios larger than 1 for the 3HDZ pathway and smaller than 1 for the NDZ pathway. There was an omeprazole concentration dependent decrease in diazepam clearance in vivo which could be modelled using a simple inhibition equation with a KI of 57 microM (19.8mg/L). In contrast there was no statistically significant change in the steady state volume of distribution for diazepam in the presence of omeprazole.
Conclusions: The in vivo KI for the omeprazole: diazepam inhibition interaction shows closer agreement with the KI values obtained in hepatocytes than with those observed in microsomes.
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http://dx.doi.org/10.1023/a:1016241000480 | DOI Listing |
J Chromatogr B Analyt Technol Biomed Life Sci
January 2024
Phase I Clinical Trial Center, Qilu Hospital of Shandong University, Jinan, China; NMPA Key Laboratory for Clinical Research and Evaluation of Innovative Drug, Shandong University, Jinan, China; School of Pharmaceutical Science, Cheeloo College of Medicine, Shandong University, Jinan, China. Electronic address:
There exist two enantiomers: (R)- and (S)-rabeprazole. (R)-rabeprazole offers specific pharmacokinetic advantages and enhanced therapeutic efficacy, warranting further investigation and development. Here, we developed a simple and rapid chiral liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to simultaneously quantify rabeprazole enantiomers and their metabolites (rabeprazole sulfoxide and desmethyl rabeprazole enantiomers) and a LC-MS to quantify rabeprazole thioether.
View Article and Find Full Text PDFFront Pharmacol
September 2022
Department of Pharmacy, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China.
Drug-induced kidney injury (DIKI) is one of the most common complications in clinical practice. Detection signals through post-marketing approaches are of great value in preventing DIKI in pediatric patients. This study aimed to propose a quantitative algorithm to detect DIKI signals in children using an electronic health record (EHR) database.
View Article and Find Full Text PDFFront Pharmacol
December 2021
Department of Pediatrics, The Third Xiangya Hospital, Central South University, Changsha, China.
Drug-induced liver injury (DILI) is a common adverse reaction in the clinic; however, there are relatively few reports of DILI in critically ill newborns and children. Making use of the Pediatric Intensive Care database (PIC), this study identifies which drugs are related to DILI in neonates and children in China. Using the PIC, we screened for patients whose liver was suspected of being injured by drugs during hospitalization.
View Article and Find Full Text PDFJ Pharm Biomed Anal
January 2021
Department of Pharmaceutical Analysis, Wuya College of Innovation, Shenyang Pharmaceutical University, No. 103, Wenhua Road, Shenyang 110016, China. Electronic address:
In order to avoid a risk of gastrointestinal toxic caused by naproxen (NAP), esomeprazole (ESOM) is generally used clinically in combination. The present work was undertaken to simultaneously determine NAP and ESOM in beagle dog plasma, and evaluated their pharmacokinetic behaviors in beagle dogs. Herein, ethyl acetate was used to extract the samples by using a time-saving evaporation-free liquid-liquid extraction (EF-LLE) method, then the samples were analyzed by supercritical fluid chromatography tandem mass spectrometry (SFC-MS/MS).
View Article and Find Full Text PDFEnviron Pollut
January 2021
Sanitation and Environmental Engineering Department, School of Engineering, Federal University of Minas Gerais, Avenue Antônio Carlos, 6627, Campus Pampulha, MG, Brazil.
The aim of the present study was to assess the risks of four different pharmaceutical active compounds (PhACs; diazepam, metformin, omeprazole and simvastatin). Acute and chronic toxicities were studied using the bacterium Aliivibrio fischeri and the microalgae Pseudokirchneriella subcapitata; while the repellency and attractiveness were assessed by avoidance tests with juvenile Cypirinus carpio using a multi-compartmented exposure system. Omeprazole was found to be an acutely toxic drug (EC: 0.
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