<unk>  contains a tricoordinated sulfinyl sulfur in a pyramidal structure and therefore can exist as either the (S)- or (R)-enantiomers.<unk>  is a racemate, an equal mixture of the two. In the acidic conditions of the canaliculi of parietal cells, both enantiomers are converted to achiral products (sulfenic acid and sulfenamide configurations) which react with a cysteine group in H+/K+ ATPase, thereby inhibiting the ability of the parietal cells to produce gastric acid. :Omeprazol rearrangement in the body AstraZeneca also developed esomeprazole (Nexium) which is a eutomer, purely the (S)-enantiomer, rather than a racemate like<unk> .<unk>  undergoes a chiral shift in vivo which converts the inactive (R)-enantiomer to the active (S)-enantiomer, doubling the concentration of the active form. This chiral shift is accomplished by the CYP2C19 isozyme of cytochrome P450, which is not found equally in all human populations. Those who do not metabolize the drug effectively are called "poor metabolizers". The proportion of the poor metabolizer phenotype varies widely between populations, from 2.0 to 2.5% in African Americans and white Americans to >20% in Asians. Several pharmacogenomics studies have suggested that PPI treatment should be tailored according to CYP2C19 metabolism status. Measurement in body fluids<unk>  may be quantified in plasma or serum to monitor therapy or to confirm a diagnosis of poisoning in hospitalized patients. Plasma<unk>  concentrations are usually in a range of 0.2–1.2 mg/l in persons receiving the drug therapeutically by the oral route and 1–6 mg/l in victims of acute overdose. Enantiomeric chromatographic methods are available to distinguish esomeprazole from racemic<unk> .
Omeprazole
Rabeprazole
Esomeprazole
Lansoprazole
Dexlansoprazole
Tenatoprazole
Pantoprazole
Ranitidine