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 This group of drugs followed and largely superseded another group of medications with similar effects, but a different mode of action, called H2-receptor antagonists.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 Essentia...

The tilde (/ˈtɪldə/; ˜ or ~) is a grapheme with several uses. The name of the character came into English from Spanish and from Portuguese, which in turn came from the Latin titulus, meaning "title" or "superscription." The reason for the name was that it was originally written over a letter as a scribal abbreviation, as a "mark of suspension", shown as a straight line when used with capitals. Thus the commonly used words Anno Domini were frequently abbreviated to Ao Dñi, an elevated terminal with a suspension mark placed over the "n". Such a mark could denote the omission of one letter or several...