OverviewDosageSide EffectsInteractionsHalf-Life

Generic Name: Omeprazole
Brands: Prilosec, Zegerid, Prilosec OTC, Zegerid OTC
Class: Proton Pump Inhibitors (PPIs)
Availability: Prescription and over the counter (OTC)
Molecular Formula: C17H19N3O3S
Substance UNII KG60484QX9

What is Omeprazole?

Omeprazole is a proton pump inhibitor (PPI). It is often sold under the brand names of Prilosec, Zegerid, Prilosec OTC, and Zegerid OTC.

What is Omeprazole Used For?

Omeprazole is used to treat heartburn that occurs two or more times a week. It is also used to treat certain stomach and esophagus problems such as ulcers, gastroesophageal reflux disease (GERD), the Zollinger-Ellison syndrome, and other indications that may be off label use.

How Does Omeprazole Work?

Omeprazole suppresses stomach acid secretion by inhibition of the enzyme found in the stomach wall that produces acid.

How Long Does it Take for Omeprazole to Work?

Prilosec OTC, the omeprazole brand that you can buy over the counter, is used for treating heartburn for up to two weeks. However, it can take 1 to 4 days to have full effect; hence it is not intended for immediate relief of heartburn. Always follow your physician’s recommendations and directions.

More severe conditions such as ulcers, GERD, and Zollinger-Ellison syndrome may take 4 to 8 weeks to heal.

Do Not Use Omeprazole If:

There are several situations where this medication may not be the right choice for you.

According to the U.S. National Library of Medicine, the following should not use omeprazole:

  • trouble or pain swallowing food
  • vomiting with blood
  • bloody or black stools
  • heartburn with light-headedness
  • sweating or dizziness
  • chest or shoulder pain with shortness of breath, pain spreading to arms, neck or shoulders
  • frequent chest pain.

Some of these symptoms may be signs of a more serious condition. Get medical help right away if you experience one or a combination of these symptoms. Please note that this list may not be complete, and there may be other situations where omeprazole use is not advisable.

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.

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