SYNONYMS HEDP; (Hydroxyethylidene) diphosphonic acid; 1-Hydroxyethane-1,1-diphosphonic acid; 1-Hydroxyethylidene-1,1-diphosphonic acid; 1-hydroxyethylidenedi(phosphonic acid); Dequest 2010; ETIDRONIC ACID CAS NO. 2809-21-4