Anatomical Therapeutic Chemical Classification System
Esomeprazole is the S-isomer of omeprazole and reduces gastric acid secretion through a specific targeted mechanism of action. Esomeprazole is a weak base and is concentrated and converted to the active form in the highly acidic environment of the secretory canaliculi of the parietal cell, where it inhibits the enzyme H+ K+ -ATPase – the acid pump and inhibits both basal and stimulated acid secretion.