The two main ways to reduce stomach acid, and when each is the better choice for heartburn.
PRILOSEC is a proton pump inhibitor (PPI) indicated for the: • Treatment of active duodenal ulcer in adults ( 1.1 ) • Eradication of Helicobacter pylori to reduce the risk of duodenal ulcer recurrence in adults ( 1.2 ) • Treatment of active benign gastric ulcer in adults ( 1.3 ) • Treatment of symptomatic gastroesophageal reflux disease (GERD) in patients 1 year of age and older ( 1.4 ) • Treatment of erosive esophagitis (EE) due to acid-mediated GERD in patients 1 month of age and older ( 1.5 ) • Maintenance of healing of EE due to acid-mediated GERD in patients 1 year of age and older ( 1.6 ) • Pathologic hypersecretory conditions in adults ( 1.7 ) 1.1 Treatment of Active Duodenal Ulcer PRILOSEC is indicated for short-term treatment of active duodenal ulcer in adults. Most patients heal within four weeks. Some patients may require an additional four weeks of therapy. 1.2 Helicobacter …
PEPCID tablets are indicated in adult and pediatric patients 40 kg and greater for the treatment of: • active duodenal ulcer (DU). • active gastric ulcer (GU). • symptomatic nonerosive gastroesophageal reflux disease (GERD). • erosive esophagitis due to GERD, diagnosed by biopsy. PEPCID tablets are indicated in adults for the: • treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, multiple endocrine neoplasias). • reduction of the risk of duodenal ulcer recurrence. PEPCID is a histamine-2 (H2) receptor antagonist indicated (1): In adult and pediatric patients 40 kg and greater for the treatment of: • active duodenal ulcer (DU). • active gastric ulcer. • symptomatic nonerosive gastroesophageal reflux disease (GERD). • erosive esophagitis due to GERD, diagnosed by biopsy. In adults for the: • treatment of pathological hypersecretory conditions (e.g., Zoll…
12.1 Mechanism of Action Omeprazole belongs to a class of antisecretory compounds, the substituted benzimidazoles, that suppress 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 irrespective of the stimulus.
12.1 Mechanism of Action Famotidine is a competitive inhibitor of histamine-2 (H2) receptors. The primary clinically important pharmacologic activity of famotidine is inhibition of gastric secretion. Both the acid concentration and volume of gastric secretion are suppressed by famotidine, while changes in pepsin secretion are proportional to volume output.
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Plain-English summaries and drug-class explainers are written and reviewed by the Priya Life Science editorial team, led by Sreepriya Prasannan (MSc Digital Transformation of Life Sciences (Innopharma Education / Griffith College); MSc & BSc Botany). Data is retrieved automatically from the sources above and cross-checked with AI-assisted verification (Anthropic's Claude) — brand and generic names are matched against the exact FDA product record so that a combination product or a different formulation cannot be mistaken for the drug on this page. An editor reviews the result before publication. We describe this in full in our editorial standards and corrections policy. The FDA data on this page was last retrieved on 8 Aug 2026.