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Prilosec vs Nexium

Omeprazole  ·  Esomeprazole

Both are proton pump inhibitors. Here is how Prilosec and Nexium compare on class, mechanism, dosing, approval and supply.

At a glance

PrilosecOmeprazole
NexiumEsomeprazole
Brand names
Prilosec / Losec
Nexium
Drug class
Proton pump inhibitor
Proton pump inhibitor
Route
Oral
Oral
Marketed by
AstraZeneca
AstraZeneca
First FDA approval
14 Sep 1989
20 Feb 2001
US shortage
Not listed
Not listed

Key differences

What each one treats

PrilosecOmeprazole

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 …

NexiumEsomeprazole

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…

How each one works

PrilosecProton pump inhibitor

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.

NexiumProton pump inhibitor

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…

Related comparisons

Prilosec VS Protonix Nexium VS Protonix Nexium VS Pepcid Prilosec VS Pepcid

Read more

Prilosec profile Nexium profile Proton Pump Inhibitors All comparisons
This is not medical advice, and not a recommendation of one drug over the other.

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.

Class and summary text is written by the Priya Life Science editorial team. Label, mechanism, route, manufacturer and approval data come from the U.S. FDA via the openFDA API; shortage status from the FDA Drug Shortage Database. Approvals, indications and brand names differ between the US, EU/Ireland (EMA/HPRA) and other regions — a drug approved in one may not be approved, or may carry a different name, in another.