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Unified Medical Language System® (UMLS®)

Vocabulary Standards and Mappings Downloads

Files marked with an asterisk (*) require a UMLS Terminology Services (UTS) account for access to downloads.

UMLS Release Name UMLS Release Description
UMLS Knowledge Sources * Current Release; archives dating from 2002. Includes Semantic Network, SPECIALIST Lexicon, and SPECIALIST Lexical Tools.
Semantic Network Open source resource that includes semantic types and semantic relations for categorizing terminologies
SPECIALIST Lexicon Open source lexicon of biomedical and general English
SPECIALIST Lexical Tools Open source set of Java programs that manage lexical variation in biomedical text

SNOMED CT Release Name SNOMED CT Release Description
SNOMED CT * International Release (RF1 and RF2 version, RF1 compatibility tools) including ICD-9-CM Cross Map; ICD-10 Cross Maps; Spanish Edition; archives dating from 2007
US Edition of SNOMED CT * Combines the SNOMED CT International Release and US Extension to SNOMED CT (terminology content accepted by the NLM as a formal extension to the International Release)
Nursing Problem List Subset of SNOMED CT * SNOMED CT encoded Nursing Problem List Subset
CORE Subset of SNOMED CT * Clinical Observations Recording and Encoding Subset of SNOMED CT
Convergent Medical Terminology (CMT) * Kaiser Permanente is donating their CMT terminology content and related tooling to the IHTSDO.

Mapping Release Name Mapping Description
SNOMED CT to ICD-10-CM Map * Mapping of US Edition of SNOMED CT to ICD-10-CM; archives dating from 2012. Published by NLM.
ICD-9-CM Diagnostic Codes to SNOMED CT Map * One-to-one and one-to-many mapping of ICD-9-CM Diagnostic Codes to US Edition of SNOMED CT; archives dating from 2012. Published by NLM.
ICD-9-CM Procedure Codes to SNOMED CT Map * One-to-one and one-to-many mapping of ICD-9-CM Procedure Codes to US Edition of SNOMED CT; archives dating from 2013. Published by NLM.

RxNorm Release Name RxNorm Release Description
RxNorm *
including Current Prescribable Content
Weekly and monthly RxNorm releases; monthly RxNorm Current Prescribable Content releases; archives dating from 2005

Last Reviewed: August 30, 2019