Proton pump inhibitors (PPIs) are medications that reduce the production of stomach acid by stopping the mechanism inside cells that pumps acid to the stomach. These drugs are generally considered to be the most effective treatment for suppressing the production of stomach acid.

PPIs are available by prescription and are used to treat conditions such as peptic ulcers, gastroesophageal reflux disease (GERD), indigestion and Zollinger-Ellison syndrome (ZES). First introduced in the 1980s, they now are considered superior to H2 blockers in terms of reducing acid production. One PPI (omeprazole) is available in an over-the-counter form.

These medications can be extremely effective at treating some conditions. For example, PPIs are the preferred method of treating GERD or Zollinger-Ellison syndrome. In some cases, these drugs are used to treat severe forms of a disease. For instance, PPIs may be used to treat gastritis when other medications fail to resolve symptoms.

PPIs provide long-lasting treatment and can be used safely for periods of 10 years or longer. They are taken once daily, preferably in the morning on an empty stomach, in a tablet or capsule form. Patients who have difficulty swallowing tablets or capsules may be urged to sprinkle granules of the drug over a tablespoon of applesauce, pudding, yogurt or cottage cheese. An intravenous (I.V.) form of PPI medication is also available.

The biggest disadvantage associated with PPIs is that they tend to be more expensive than other, similar medications. However, this cost may be offset by the fact that PPIs usually require lower and less frequent dosing than drugs such as H2 blockers.

All PPIs work similarly to one another, and there is no evidence to support the use of one type over another. They do, however, differ in their drug interactions and how they are processed by the liver. In addition, some PPIs demonstrate longer lasting effects and therefore may be taken less frequently.

Types of PPIs include: