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RxNorm Aligns with International Drug Models by Adding New Attributes

RxNorm Aligns with International Drug Models by Adding New Attributes. NLM Tech Bull. 2018 Sep-Oct;(424):b6.

September 06, 2018 [posted]

The National Library of Medicine (NLM) is pleased to announce the addition of basis of strength substance (BoSS) related attributes in RxNorm beginning with the September 2018 release. These new attributes better align RxNorm with global drug information standards, such as the new SNOMED CT Drug Model and Identification of Medicinal Products (IDMP) used by the European Medicines Agency (EMA), marking a milestone towards achieving global interoperability for medicinal products.

The RXN_BOSS_FROM attribute explicitly identifies the active ingredient or active moiety in a drug product that is measured to provide the drug strength. Previously, the basis of strength substance was implied in the fully specified RxNorm normalized name. The new attributes now indicate the basis of strength substance and additional drug information on the Semantic Clinical Drug Component (SCDC) term type in the SAB=RXNORM data source. The new attributes also support computation by including the product strength as discrete numerator and denominator values and units rather than as a string in the RxNorm normalized name.

There are seven new attribute names (ATN) in RXNSAT associated with SCDC term types in RxNorm. The new attribute descriptions are available in Appendix 4 – RxNorm Attributes.

RXN_BOSS_AI
RXN_BOSS_AM
RXN_BOSS_FROM
RXN_BOSS_STRENGTH_DENOM_UNIT
RXN_BOSS_STRENGTH_DENOM_VALUE
RXN_BOSS_STRENGTH_NUM_UNIT
RXN_BOSS_STRENGTH_NUM_VALUE

NLM would like to thank those involved for implementing the new attributes. This is a major step towards aligning the RxNorm standard vocabulary with international standards.