Proton-pump inhibitors are a class of antacids that work by preventing the formation of stomach acid by the stomach lining. They are used in the treatment of gastric ulcers and acid reflux disease. They are generally not used for intermittent heartburn as they have to be taken well in advance of eating (at least thirty minutes) in order to be effective.
Proton-pump inhibitors are one of the most commonly prescribed types of pharmaceuticals in the United States. They are effective in almost all patients, and have very minor side effects. They largely replaced a less effective type of acid inhibiting drug known as an H2 receptor antagonist. The previous drug would block some acid production, but proton-pump inhibitors block about 99% of acid production.
Proton-pump inhibitors work by blocking one of the enzymes that occur in stomach lining cells that are involved in acid production, in particular the enzyme involved in the final step before the acid is created. The inhibitor permanently binds to the enzyme, rendering it permanently disabled.
One of the side effects of the drugs is they tend to protect kidney function, particularly from bacteriological infection. However, they can also encourage the development of pneumonia and clostridium perfringens and must be used in moderation with patients at risk for these conditions. Patients can also become dependent on the drug and will suffer a relapse if the use of the drug is discontinued.