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New UMLS REST API

New UMLS REST API. NLM Tech Bull. 2015 Nov-Dec;(407):b3.

November 05, 2015 [posted]

NLM is pleased to announce a new UMLS REST API-beta version. This development is in response to UMLS users who have indicated on their UMLS Annual Report an interest in a REST API to search and retrieve UMLS data over the Web.

The current implementation of the REST API supports the most frequently needed use cases such as:


  • Searching a term and retrieving UMLS CUIs;
  • Retrieving information for a CUI such as names, semantic type(s), atoms, definitions, etc.;
  • Retrieving information for source-asserted identifiers (e.g. from SNOMED CT, LOINC, MeSH, etc.) such as names, parents, children, descendants, atoms, and other relations; and
  • Extracting subsets, such as the SNOMED CT to ICD-10-CM map.

Additional features are in development.

Sample code is available on GitHub to help users get started interacting with the API in common languages such as Python, Perl, and Java.

Please send your feedback to NLM Customer Service and use "UMLS REST API feedback" in your subject line.

We also welcome general comments and discussion regarding the API on the UMLS listserv.