Proton pump inhibitors (PPIs) are a class of drugs that reduce the amount of stomach acid made by glands in the lining of the stomach. They work by irreversibly blocking an enzyme called H+/K+ ATPase which controls acid production. PPIs are used to treat conditions that are caused by either an overproduction of stomach acid or exacerbated by stomach acid, such as acid reflux, gastroesophageal reflux disease (GERD), and peptic ulcer disease. PPIs are available in both prescription and over-the-counter forms, and there are many names and brands of PPIs available. Some common PPIs include omeprazole (Prilosec), esomeprazole (Nexium), lansoprazole (Prevacid), rabeprazole (AcipHex), pantoprazole (Protonix), and dexlansoprazole (Dexilant) . When taken at the recommended dosage for the recommended duration of time, PPIs are considered safe. However, they can cause adverse reactions such as headaches, dizziness, skin rash, abdominal pain, diarrhea, back pain, and upper respiratory infections. It is important to note that overuse of PPIs can lead to potential adverse effects, and it is recommended to take the lowest effective dose for the shortest duration of time.