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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
RXN_BOSS_AI Attribute of Semantic Clinical Drug Component (SCDC) atom referring to the active ingredient name.

The Basis of Strength Substance (BoSS) is the active ingredient or active moiety in a drug product that is measured to provide the product strength.

An active ingredient is any component that provides pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease, or to affect the structure or any function of the body of man or animals.
Active ingredient name Hydrocortisone
Warfarin Sodium
RXN_BOSS_AM Attribute of SCDC atom referring to the active moiety name.

An active moiety is the part of a drug that makes the drug work the way it does. More specifically, the active moiety is the molecule or ion, excluding portions of the molecule that cause the drug to be an ester, salt, or other noncovalent derivative of the molecule, responsible for the physiological or pharmacological action of the drug substance.
Active moiety name Aspirin
Dextromethorphan
Fluoxetine
RXN_BOSS_FROM Attribute of SCDC atom referring to the source of the BoSS as either from the active ingredient or the active moiety. “AI” or “AM” AI
AM
RXN_BOSS_STRENGTH_DENOM_UNIT Attribute of SCDC atom indicating the dosage unit of the strength (e.g. tablets and capsules default to 1). Unit of measure MG
ML
HR
RXN_BOSS_STRENGTH_DENOM_VALUE Attribute of SCDC atom indicating the number of denominator units for each numerator strength value (e.g. tablets and capsules default 1). Number 5
1
RXN_BOSS_STRENGTH_NUM_UNIT Attribute of SCDC indicating the unit of measure for the medicinal product strength. Unit of measure MG
MEQ
ML
RXN_BOSS_STRENGTH_NUM_VALUE Attribute of SCDC indicating the strength of the BoSS. Number 25
0.001
NDC National Drug Code (NDC) value normalized from source-asserted NDC 11-digit, no dashes, HIPAA formatted normalized NDC 58016069367
00781199213
ORIG_CODE Source code (CODE) of original source atom from which RxNorm concept was created; Found in RXNSAT for some DF and ET atom attributes which were originally from HL7 CODE HL7T096
U000013
ORIG_SOURCE Source abbreviation (SAB) of original source atom from which RxNorm concept was created; Found in RXNSAT for some DF and ET atom attributes which were originally from HL7 SAB NDDF
MDDB
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_QUALITATIVE_DISTINCTION Qualitative modifiers used to distinguish between concepts, attributed to SCD and SBD atoms String Microencapsulated
Sugar-Free
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

Last Reviewed: September 4, 2018