Description
Mechanism of Action
Omeprazole is a substituted benzimidazole gastric antisecretory agent and is also known as PPI. It blocks the final step in gastric acid secretion by specific inhibition of H+/K+ ATPase enzyme system present on the secretory surface of the gastric parietal cell. Both basal and stimulated acid are inhibited.
Onset: Approx 1 hr.
Duration: Up to 72 hr.
Absorption: Rapid but variably absorbed (oral). Bioavailability: Oral: Approx 30-40%. Time to peak plasma concentration: Approx 1-2 hr.
Distribution: Plasma protein binding: Approx 95%.
Metabolism: Hepatic metabolism via CYP2C19 isoenzyme to form hydroxyl-omeprazole and CYP3A4 to form omeprazole sulfone.
Excretion: Mainly via urine (approx 77%), the remainder in faeces (via the bile). Elimination half-life: 0.5-3 hr.
MIMS Class
Antacids, Antireflux Agents & Antiulcerants
ATC Classification
A02BC01 – omeprazole; Belongs to the class of proton pump inhibitors. Used in the treatment of peptic ulcer and gastro-oesophageal reflux disease (GERD).;
