Omeprazole is in a class of drugs called proton pump inhibitors (PPI) which block the production of acid by the stomach. Other drugs in the same class include lansoprazole (Prevacid), rabeprazole (Aciphex), pantoprazole (Protonix), and esomeprazole (Nexium). Proton pump inhibitors are used for the treatment of conditions such as ulcers, gastroesophageal reflux disease (GERD) and the Zollinger-Ellison Syndrome which are all caused by stomach acid. Omeprazole, like other proton-pump inhibitors, blocks the enzyme in the wall of the stomach that produces acid. By blocking the enzyme, the production of acid is decreased, and this allows the stomach and esophagus to heal.
Omeprazole is an oral antiulcer agent. It is indicated for short term therapy of gastroesophageal reflux disease, gastric and duodenal ulcers, and gastric hypersecretory conditions including Zollinger-Ellison syndrome, systemic mastocytosis, and multiple endocrine adenoma. Unlike other antiulcer agents, omeprazole does not antagonize HA or cholinergic receptors. Omeprazole has a long duration of action and a high level of potency, allowing for once-daily administration. Omeprazole belongs to a new class of antisecretory agents, the substituted benzimidazoles, which suppress gastric acid secretion by inhibiting the H+/K+ ATPase enzyme system of parietal cells. Following activation in an acidic pH, omeprazole binds irreversibly to the H+/K+ ATPase pump on the secretory surface of the parietal cell membrane. Subsequently, the secretion of hydrogen ions into the gastric lumen is inhibited. Omeprazole is characterized as a gastric acid pump inhibitor because it blocks the final step of gastric acid production. It inhibits both basal and stimulus-induced acid secretion. Omeprazole is an extremely potent drug. Intragastric pH of patients receiving omeprazole is often higher and affected longer than during therapy with HA-antagonists. Omeprazole is also more effective than either HA-antagonists or sucralfate in the treatment of gastroesophageal reflux disease (GERD).
Omeprazole can be used to prevent and treat peptic ulcers that can occur as a side effect of non-steroidal anti-inflammatory drugs (NSAIDs), such as diclofenac. In addition it can relieve side effects such as indigestion that can be associated with these medicines. Omeprazole is used for treating acid-induced inflammation and ulcers of the stomach and duodenum, gastroesophageal reflux disease (GERD) and Zollinger-Ellison Syndrome. It also is used in combination with antibiotics for eradicating H. pylori infection of the stomach. Omeprazole is also given together with antibiotics to help eradicate bacteria called Helicobacter pylori from the stomach. These bacteria can contribute to the formation of peptic ulcers. Omeprazole helps create an environment in the gut in which the antibiotics can be more effective at killing the bacteria. Omeprazole is used in varying doses and for varying lengths of time depending on the condition being treated.