Types of medicine
What Is a Proton Pump Inhibitor (PPI)? Uses and Warnings
Proton pump inhibitor · say it: PROH-ton PUMP in-HIB-ih-terAlso written: PPI, PPIs, acid reducer
Short answer
A proton pump inhibitor (PPI) is a medicine that greatly reduces stomach acid. Names usually end in '-prazole', like omeprazole.
What it means
Proton pumps are tiny pumps in the stomach lining that release acid. PPIs switch many of them off, so much less acid is made. Examples include omeprazole, esomeprazole, lansoprazole and pantoprazole. They are used for heartburn, GERD, stomach and duodenal ulcers, clearing H. pylori (with antibiotics), and protecting the stomach during NSAID use.
Labels explain several points. Over-the-counter PPIs are for frequent heartburn for a limited course, as printed on the pack; if you need them longer, see a doctor. Prescription labels mention possible effects of long-term use, such as low magnesium, low vitamin B12, bone fractures and C. diff diarrhea, and some interactions, for example with clopidogrel and some HIV medicines. Trouble swallowing, vomiting blood or black stools need prompt medical attention.
PPIs are stronger acid reducers than H2 blockers (such as famotidine) and work differently from antacids, which neutralise acid that is already there.
Where you may see it
- 'Indications' and 'Warnings' sections of omeprazole and pantoprazole labels
- Over-the-counter PPI 'Drug Facts' panel ('14-day course')
- Medication reviews in older adults
📄 How it looks on a report
Long-term PPI therapy may be associated with an increased risk of osteoporosis-related fractures. Use the lowest dose and shortest duration appropriate to the condition.
🙅 What it does not mean
- The long-term warnings do not mean short courses are risky for most people.
- A PPI is not the same as an antacid and does not work instantly.
- It does not mean you should stop suddenly after long use; ask about reducing gradually.
🎯 Check yourself
Which of these is the right meaning of “Proton pump inhibitor”?
🗒️ Questions to ask your doctor
💊 Medicines whose labels mention “Proton pump inhibitor”
Plain-English explanations of each medicine, from its official FDA label.
- Esomeprazole
An acid reducer. The label gives this as its purpose, and no specific drug class is listed.
- Famotidine
A histamine-2 (H2) receptor blocker, a type of medicine that lowers stomach acid.
- Omeprazole
a proton pump inhibitor (PPI), a type of medicine that lowers the amount of acid in the stomach
- Pantoprazole
a proton pump inhibitor (PPI), a medicine that reduces the amount of acid the stomach makes
🔗 Read more from trusted sources
- “Proton pump inhibitor” on MedlinePlus ↗
US National Library of Medicine
- NCI Dictionary definition ↗
US National Cancer Institute: “proton pump inhibitor”
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