Leveprazole Mechanism of Action

Pharmacology: Pharmacodynamics: Omeprazole is a proton pump inhibitor that belongs to a class of antisecretory compounds, the substituted benzimidazoles. It suppresses gastric acid secretion by specific inhibition of the H /K ATPase enzyme system at the secretory surface of the gastric parietal cell. Because this enzyme system is regarded as the acid (proton) pump within the gastric mucosa, Omeprazole has been characterized as a gastric acid-pump inhibitor, in that it blocks the final step of acid production.
This effect is dose-related and leads to inhibition of both basal and stimulated acid secretion.
Pharmacokinetics: Distribution: The apparent volume of distribution in healthy subjects is approximately 0.3 L/kg body weight. Omeprazole is 97% plasma protein bound.
Elimination: Total plasma clearance is about 30 to 40 L/h after a single dose. The plasma elimination half-life of Omeprazole is usually shorter than one hour both after single and repeated once-daily dosing. Omeprazole is completely eliminated from plasma between doses with no tendency for accumulation during once-daily administration. Almost 80% of a dose of Omeprazole is excreted as metabolites in the urine, the remainder in the feces, primarily originating from bile secretion.
Special populations: Hepatic impairment: The metabolism of Omeprazole in patients with liver dysfunction is impaired, resulting in an increased AUC. Omeprazole has not shown any tendency to accumulate with once-daily dosing.
Renal impairment: The pharmacokinetics of Omeprazole, including systemic bioavailability and elimination rate, are unchanged in patients with reduced renal function.
Older people: The metabolism rate of Omeprazole is somewhat reduced in elderly subjects (75 to 79 years of age).