Gastric acid inhibitors drugs

The anti-ulcer agents omeprazole, lanzoprazole, and pantoprazole have been introduced during the past decade for the treatment of peptic ulcers. Gastric acid secretion is efficiently reduced by prazole inhibition of H+K+-ATPase in the parietal cells of the gastrointestinal mucosa [75]. The prazoles themselves are not active inhibitors of the enzyme, but are transformed to cyclic sulfenamides in the intracellular acidic compartment of parietal cells [76]. The active inhibitors are permanent cations at pH < 4, with limited possibilities of leaving the parietal cells, and thus are retained and activated at the site of action. In the neutral body compartments the prazoles are stable, and only trace amounts are converted to the active drugs. (For a review on omeprazole, see Ref. [77].)... 

Some sugar-derived dmgs obtained by chemical means have also achieved some importance, for example, ranitidine (Zantac ), an inhibitor of gastric acid secretion—one of the top 30 drugs based on sales —isosorbide dinitrate, a coronary vasodilatator, or topiramate, a fructose-derived anticolvulsant drug with high antiepileptic efficacy. ... 

Omeprazole is an antiulcer drug. It is a proton pump inhibitor. This substituted benzimidazole inhibits gastric acid secretion to help acid/peptic disorders and duodenal ulcers. It interferes with the proton pump in the mucous lining of the stomach, the last stage of acid production. It can turn off stomach acid in as little as one hour. Lansoprazole (no. 12) has a similar structure. 

Proton pump inhibitors cause a profound and long-lasting inhibition of gastric acid secretion therefore, proton pump inhibitors may interfere with the absorption of drugs where gastric pH is an important determinant of bioavailability (eg, ketoconazole, ampicillin, iron salts, digoxin, cyanocobalamin). 

Pantoprazole sodium, a substituted benzimidazole derivative, is an irreversible proton pump inhibitor, and was developed for the treatment of acid-related gastrointestinal disorders. As with other drugs of its class (e. g. omeprazol or lansoprazole), pantoprazole reduces gastric acid secretion through inhibition of the portion on the gastric parietal cell. In combination with other drugs, pantoprazole can be used for the initial treatment of H. Pylori infection [1],... 

Omeprazole [om ME pary zol] is the first of a new class of drugs that binds to the H7K+-ATPase enzyme system (proton pump) of the parietal cell, suppressing secretion of hydrogen ions into the gastric lumen. The membrane-bound proton pump is the final step in the secretion of gastric acid (see Figure 24.3). A second proton pump inhibitor, lansoprazole [Ian SOP ra zol], is also available. 

Ranitidine is about four times more potent than cimetidine in man as an inhibitor of gastric acid secretion [11], and in 1981 was marketed as Zantac . Ranitidine is not only more potent than cimetidine but also proved to be more selective. Cimetidine also inhibits cytochrome P-450, an important drug-metabolizing... 

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