A Critical Appraisal of Enantiomer Concept of Proton Pump Inhibitors.

Proton pump inhibitors (PPIs) one of the most prescribed drugs worldwide, inhibit acid secretion in the stomach by irreversible hydrogen/potassium adenosine triphosphatase (H+/K+ ATPase) blocking. Currently conventional PPIs in markets are mainly in racemic forms (containing both R- and S- forms). It has been suggested that the beneficial effects of racemic PPIs mostly depend on one of the enantiomers, and a drug containing pure enantiomers might be superior to racemic PPIs. Enantiomers are mirror image stereoisomers of a molecule. In this article, we aim to analyze the comparative studies of the enantiomers of PPIs with non-racemic counter-parts and to assess whether enantiomers, as suggested by certain studies and primarily promoted by some pharmaceutical companies, demonstrate superior efficacy.