RxNorm

RxNorm is a standardized drug nomenclature system produced and maintained by the U.S. National Library of Medicine (NLM). It provides normalized names for clinical drugs and links each drug name to many of the drug vocabularies commonly used in pharmacy management, health information exchange, and electronic prescribing systems. RxNorm serves as a common language that enables different systems to communicate drug information unambiguously.

The RxNorm vocabulary organizes drug information at multiple levels of specificity, from ingredient level (e.g., "acetaminophen") to clinical drug level (e.g., "acetaminophen 500 MG Oral Tablet") to branded drug level (e.g., "Tylenol 500 MG Oral Tablet"). Each concept receives a unique RxCUI (RxNorm Concept Unique Identifier) that serves as a stable, system-independent reference for that drug concept.

RxNorm plays a critical role in healthcare interoperability. When prescription data is exchanged between systems, such as from an EHR to a pharmacy management system, RxNorm codes ensure that both systems are referring to the exact same drug product, regardless of differences in how each system represents medication names internally. This is essential for accurate drug interaction checking, formulary matching, and clinical decision support.

Electronic prescribing platforms and medication catalogs map their drug databases to RxNorm concepts to enable cross-system data exchange and to leverage RxNorm-based clinical tools. The terminology is updated monthly and is freely available, making it a foundational component of the U.S. healthcare data infrastructure.