Both are proton pump inhibitors. Here is how Nexium and Protonix compare on class, mechanism, dosing, approval and supply.
NEXIUM is a proton pump inhibitor (PPI). NEXIUM delayed-release capsules and NEXIUM for delayed-release oral suspension are indicated for the: • Short-term treatment in the healing of erosive esophagitis (EE) in adults and pediatric patients 12 years to 17 years of age. ( 1.1 ) • Maintenance of healing of EE in adults. ( 1.2 ) • Short-term treatment of heartburn and other symptoms associated GERD in adults and pediatric patients 12 years to 17 years of age. ( 1.3 ) • Risk reduction of nonsteroidal anti-inflammatory drugs (NSAID)-associated gastric ulcer in adults at risk for developing gastric ulcers due to age (60 years and older) and/or documented history of gastric ulcers. ( 1.4 ) • Helicobacter pylori eradication in adult patients to reduce the risk of duodenal ulcer recurrence in combination with amoxicillin and clarithromycin. ( 1.5 ) • Long-term treatment of pathological hypersec…
An oral or intravenous medication used to treat acid reflux and erosive esophagitis.
12.1 Mechanism of Action Esomeprazole 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. Esomeprazole is protonated and converted in the acidic compartment of the parietal cell forming the active inhibitor, the achiral sulphenamide. Because this enzyme system is regarded as the acid (proton) pump within the gastric mucosa, esomeprazole 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 stim…
An oral or intravenous medication used to treat acid reflux and erosive esophagitis.
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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 5 Aug 2026.