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Unified Medical Language System® (UMLS®)

Contact UMLS, Value Set Authority Center, or SNOMED CT Support:

Contact RxNorm Support:

Contact RxNav Support:

UMLS Users Listserv (UMLSUSERS-L):

UMLS users are encouraged to subscribe to this list, to share their experiences with, or seek advice from the UMLS community on using UMLS resources. NLM also uses this forum to distribute official announcements about UMLS products and services.

RxNorm Announcements Listserv (RXNORM-ANNOUNCES-L):

Announcement-only list about major changes to the RxNorm release files, technical issues related to accessing the files, and other important announcements.

VSAC Announcements Listserv (NLM_VSAC_UPDATES):

Announcement-only list about new releases and other communications related to the activities of the Value Set Authority Center (VSAC).

SNOMED CT Announcements Listserv (SNOMEDCT-ANNOUNCES-L):

Announcement-only list about major changes to the SNOMED CT release files, technical issues related to accessing the files, and other important announcements.

Last Reviewed: November 2, 2020