PPI stands for proton pump inhibitor, which is a type of medication that reduces the amount of stomach acid produced by glands in the lining of the stomach. PPIs are used to treat a variety of conditions related to stomach acid, including acid reflux, gastroesophageal reflux disease (GERD), and stomach ulcers. They are available both over-the-counter and with a prescription, and are taken orally in the form of tablets or capsules. Common PPIs include lansoprazole (Prevacid), omeprazole (Prilosec), pantoprazole (Protonix), rabeprazole (AcipHex), and esomeprazole (Nexium) . While PPIs are generally considered safe, there are potential side effects associated with long-term use, including an increased risk of infections, bone fractures, and kidney disease. It is important to talk to a healthcare provider about the risks and benefits of taking PPIs, and to use them only as directed.