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Unified Medical Language System® (UMLS®)

Appendix 4 - RxNorm Attributes
ATN Description ATV ATV Example(s)
AMBIGUITY_FLAG Attribute of atom that has been duplicated; Original atom is "Base" and duplicate atoms are "Duplicate" "Base" or "Duplicate" Base
Duplicate
NDC National Drug Code (NDC) value normalized from source-asserted NDC 11-digit, no dashes, HIPAA formatted normalized NDC 58016069367
00781199213
ORIG_AMBIGUITY_FLAG Attribute of original source atom that was duplicated while before becoming obsolete; Only found in RXNSATOCD "Base" Base
ORIG_CODE Source code (CODE) of original source atom from which RxNorm concept was created; Only found in RXNSATOCD, except for some DF and ET atom attributes in RXNSAT which were originally from HL7 CODE HL7T096
U000013
ORIG_SOURCE Source abbreviation (SAB) of original source atom from which RxNorm concept was created; Only found in RXNSATOCD, except for some DF and ET atom attributes in RXNSAT which were originally from HL7 SAB NDDF
MDDB
ORIG_TTY Term type (TTY) of original source atom from which RxNorm concept was created; Only found in RXNSATOCD TTY FN
CDD
ORIG_VSAB Versioned source abbreviation (VSAB) of original source atom from which RxNorm concept was created; Only found in RXNSATOCD VSAB GS_2008_02_07
MTHSPL_2010_04_02
RXN_ACTIVATED Date when an atom was reactivated from SUPPRESS=O to SUPPRESS=N Date 01/28/2010
11/02/2007
RXN_AVAILABLE_STRENGTH Strength value of SCDG and SBDG atoms for all available strengths of an ingredient at the SCD/SBD level; Also strength value of SCD and SBD atoms Number followed by a unit of measure 10 MG/ML
0.154 MEQ/ML
RXN_BN_CARDINALITY Attribute of BN atom that refers to the number of ingredients it contains "single" or "multi" single
multi
RXN_HUMAN_DRUG Attribute of BPCK, GPCK, SBD, SCD, or BN atom intended for human use and the country in which the drug is marketed for that purpose; Only applied for US drugs at this time International Organization for Standardization (ISO) 3166-1-alpha-2 country code US
RXN_IN_EXPRESSED_FLAG Attribute of SCDC atom that is expressed as precise ingredient (TTY=PIN); SCDC atom will have RELA=has_precise_ingredient to a TTY=PIN atom in RXNREL "P" P
RXN_OBSOLETED Date when an atom was changed from SUPPRESS=N to SUPPRESS=O; Attribute of BPCK, GPCK, SBD, SCD, SBDC, SCDC, SBDF, SCDF, or DF atom that has no source-asserted atoms and no relationships to SUPPRESS=N atoms Date 09/14/2005
08/30/2007
RXN_QUANTITY Factors of time, measures or strength attributed to SCD and SBD atoms Number followed by a unit measure; Could be a strength, unit of time, or quantity of dosages 12 HR
120 ACTUAT
RXN_STRENGTH Strength value of SCDC atoms Number followed by a unit of measure 250000 UNT
0.00833 MG/HR
RXN_VET_DRUG Attribute of BPCK, GPCK, SBD, SCD, or BN atom intended for veterinary use and the country in which the drug is marketed for that purpose; Only applied for US drugs at this time International Organization for Standardization (ISO) 3166-1-alpha-2 country code US
RXTERM_FORM Drug application interface-friendly dose form attribute of SCD and SBD atoms Dose form string Tab
Gel
UMLSAUI Unified Medical Language System (UMLS) atom unique identifier (AUI) applied to atom during the most recent UMLS release UMLS AUI A15550595
A1537190
UMLSCUI Unified Medical Language System (UMLS) concept unique identifier (CUI) applied to atom during the most recent UMLS release UMLS CUI C1176718
C1599949
UNII_CODE Unique ingredient identifier (UNII) from the U.S. Food and Drug Administration (FDA) UNII code TL2TJE8QTX
LQU92IU8LL

Last Reviewed: December 3, 2012