Nexium vs Protonix
Both are proton pump inhibitors. Here is how Nexium and Protonix compare on class, mechanism, dosing, approval and supply.
At a glance
Key differences
- Same class. Both Nexium and Protonix are proton pump inhibitors, so they work through the same broad mechanism. Differences between them tend to be about dosing, route, how selective they are, and side effects rather than what they target.
- Time on the market. Nexium was first approved by the FDA in 2001, Protonix in 2000.
- Who markets them. Nexium is marketed by AstraZeneca; Protonix by Wyeth (Pfizer).
What each one treats
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.
How each one works
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.
Related comparisons
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Which medicine is right for a given person depends on their diagnosis, other conditions, other medicines, kidney and liver function, pregnancy, and cost or reimbursement — none of which this page knows. Two drugs in the same class are not automatically interchangeable. Never start, stop or switch a prescription medicine on the basis of a web page; that decision belongs to you and your clinician or pharmacist.
How this page is built
The facts on this page are pulled directly from official U.S. FDA datasets — they are not written from memory. Each field below names the dataset it came from, so you can check it yourself.
- FDA Drug Label (openFDA) ↗ Indications, mechanism of action and pharmacologic class
- Drugs@FDA ↗ First FDA approval date and the company holding the application
- FDA Drug Shortage Database ↗ Current US supply / shortage status
Plain-English summaries and drug-class explainers are written and reviewed 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 Oct 2026. How every register is built: methodology · fixes we have made: corrections log.