This document discusses the antibiotic benzathine benzylpenicillin G, also known as Pencitard vial I.M. It works by inhibiting the formation of cell walls in bacteria through similarity of steriochemistry between its beta lactam structure and the D-Alanyl D-Alanine amino acids. While it can be broken down by beta-lactamases, it has a high molecular weight and is not acid labile, allowing it to be administered intramuscularly rather than orally or intravenously to treat bacterial infections. Care must be taken when injecting to avoid neurovascular damage.
