Proton pump inhibitors

Proton-pump inhibitor
Drug class
General structure of a proton-pump inhibitor
Class identifiers
Use	Reduction of gastric acid production
ATC code	A02BC
Mechanism of action	Enzyme inhibitor
Biological target	H+/K+ ATPase
Clinical data
Drugs.com	Drug Classes
WebMD	MedicineNet
External links
MeSH	D054328

Proton pump inhibitors (PPIs) are a group of drugs whose main action is a pronounced and long-lasting reduction of gastric acid production. Within the class of medications, there is no clear evidence that one agent works better than another.

They are the most potent inhibitors of acid secretion available. This group of drugs followed and largely superseded another group of medications with similar effects, but a different mode of action, called H₂-receptor antagonists.

PPIs are among the most widely sold drugs in the world, and the first one, omeprazole, is on the WHO Model List of Essential Medicines. The cost between different agents varies significantly.

These drugs are used in the treatment of many conditions, such as:

Specialty professional organizations recommend that people take the lowest effective PPI dose to achieve the desired therapeutic result when used to treat gastroesophageal reflux disease long-term. In the United States, the Food and Drug Administration has advised that no more than three 14-day treatment courses should be used in one year.

Despite their extensive use, the quality of the evidence supporting their use in some of these conditions is variable. The effectiveness of PPIs has not been demonstrated for every case. For example, although they reduce the incidence of esophageal adenocarcinoma in Barrett's oesophagus, they do not change the length affected.

In general, proton pump inhibitors are well tolerated, and the incidence of short-term adverse effects is relatively low. Long-term use of PPIs has been less studied than short-term use, and the lack of data makes it difficult to make definitive statements. The range and occurrence of adverse effects are similar for all of the PPIs, though they have been reported more frequently with omeprazole. This may be due to its longer availability and, hence, clinical experience.

Common adverse effects include headache, nausea, diarrhea, abdominal pain, fatigue, and dizziness. Infrequent adverse effects include rash, itch, flatulence, constipation, anxiety, and depression. Also infrequently, PPI use may be associated with occurrence of myopathies, including the serious reaction rhabdomyolysis.