Proton Pump Inhibitors (PPIs): Uses & Side Effects

PPIs reduce the production of acid by the stomach. They work by irreversibly blocking an enzyme called H+/K+ ATPase which controls acid production. This enzyme is also known as the proton pump and is found in the parietal cells of the stomach wall.


PPIs treat conditions that are caused by either an overproduction of stomach acid or exacerbated by stomach acid. Taking a PPI once a day inhibits around 70% of proton pumps, so a small amount of acid is still available for food digestion.

PPIs may be used for the treatment of:

  • Acid reflux, also called gastroesophageal reflux disease (GERD)
  • Conditions characterized by an overproduction of stomach acid (such as Zollinger-Ellison syndrome)
  • Duodenal or stomach ulcers including those caused by NSAIDs
  • In combination with certain antibiotics for the eradication of Helicobacter pylori, a bacteria associated with duodenal ulcer recurrence
  • Erosive esophagitis, and to maintain healing of erosive esophagitis.

Side effects

PPIs are generally well tolerated. The more common side effects reported with their use include:

  • A headache
  • Fever
  • Gastrointestinal effects (such as abdominal pain, constipation, diarrhea, flatulence, nausea, or vomiting)
  • Light-headedness
  • Magnesium or vitamin B12 deficiency (usually only with long-term administration)
  • Rash
  • Tongue discoloration or taste disturbances.

Keywords: proton pump inhibitors; PPIs.

* The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.