Na4HEDP ; Tetrasodium (1-hydroxyethylidene)bisphosphonate; Tetra Sodium Salt of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid; ETIDRONIC ACID, TETRASODIUM SALT; 1-Hydroxyethane-1,1-diphosphonic acid , Tetrasodium salt; 1-Hydroxyethylidene-1,1-diphosphonic acid, Tetrasodium salt; Sodium HEDP; HEDPS; 1-hydroxyethylidenedi(phosphonic acid), Tetrasodium salt; (Hydroxyethylidene) diphosphonic acid, Tetrasodium salt; Tetra Sodium Salt of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid; CAS NO:3794-83-0