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VSAC Support Center

Code Systems and Tools


This table displays all of the available code systems currently supported by the Value Set Authority Center for the purpose of authoring and maintaining value sets. Currently, all available code systems are covered by the terms of the UMLS Metathesaurus® License Agreement, and all users of VSAC are required to obtain a UMLS License and abide by the terms of the license.

Learn more about VSAC code systems: CDCREC, CDT, CPT®, CVX, HCPCS, ICD-10-CM, ICD-10-PCS, ICD-9-CM, LOINC®, NCI,
NDF-RT, NUCC-PT, RxNorm, SNOMED CT®, SOP


RxNorm: VSAC releases RxNorm version updates monthly on the third Monday of the month. For example, when RxNorm releases the monthly update on 11/07/2016, VSAC will provide this release in VSAC by the third Monday of November, 11/21/2016.

All other VSAC terminologies: In most cases, when a VSAC terminology publishes an updated version, barring any data issues or inconsistencies that require resolution with the source terminology, UMLS needs approximately 3 weeks to process the update into VSAC-consumable files. VSAC needs about 3 weeks processing time after receiving the UMLS-processed files. This is the time it takes VSAC to extract, transform, load, and perform quality assurance for the code system. Total time from source terminology update to VSAC publication, approximately six weeks.

  • NLM Tools for EHR Certification and Meaningful Use
  • UMLS Terminology Services
  • U.S. SNOMED CT® Content Request System (USCRS)
  • RxMix : RxMix is an interface for building applications that allows users to combine functions of the RxNorm, RxTerms, and NDF-RT APIs. RxMix offers several notable features: function composition; batch processing; output in XML, JSON or Text; interactive mode for testing workflows.
  • RxClass: The RxClass Browser is a web application for exploring and navigating through the class hierarchies to find the RxNorm drug members associated with each class.
  • RxNav : RxNav is a browser for several drug information sources, including RxNorm, RxTerms and NDF-RT. RxNav finds drugs in RxNorm from the names and codes in its constituent vocabularies.