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New Tutorial: UMLS REST API: Authentication and Calling

New Tutorial: UMLS REST API: Authentication and Calling. NLM Tech Bull. 2017 May-Jun;(416):b10.

June 26, 2017 [posted]

The National Library of Medicine (NLM) is pleased to announce the release of the UMLS REST API: Authentication and Calling video tutorial. The tutorial describes the three steps required to successfully retrieve Unified Medical Language System (UMLS) data using the Application Programming Interface (API):


  1. Obtain a Ticket Granting Ticket (TGT). This process requires UMLS authentication. The TGT can be reused for an unlimited number of times within 8 hours after being generated.
  2. Use the TGT to generate single-use Service Tickets, or ST, that can be used to place only one API call, and is valid for 5 minutes.
  3. Make the API call to retrieve UMLS Terminology Services (UTS) data.

These three steps are demonstrated in the tutorial using Postman, a popular API testing application.

This tutorial and many other tutorials are available from the UMLS Learning Resources page and the NLM Learning Resources Database.