What is the mechanism of action of omeprazole?

Omeprazole specifically acts by inhibiting the H+/K+ ATPase enzyme located in the parietal cells of the gastric mucosa. This enzyme is responsible for secreting hydrogen ions (protons) into the gastric lumen, which is a key step in the production of gastric acid. By blocking this proton pump mechanism, omeprazole effectively reduces the overall acidity in the stomach, leading to decreased gastric acid secretion and providing relief from conditions like gastroesophageal reflux disease (GERD) and peptic ulcers.

The action of omeprazole is significant because it directly targets the final step in acid production, making it a potent proton pump inhibitor (PPI). This mechanism is crucial for treating acid-related disorders, as it provides long-lasting suppression of gastric acid secretion compared to other medications that may only temporarily reduce acidity.