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Check out the Postman sample collection to help you get started using the UMLS REST API.

API Terms of Service

User Authentication

The UMLS REST API requires a UMLS account for the authentication described below. If you do not have a UMLS account, you may apply for a license on the UMLS Terminology Services (UTS) website.

Step 1: Get your API key from your UTS profile.

Step 2: Append your API key to a data request.

For example, https://uts-ws.nlm.nih.gov/rest/content/current/CUI/C0009044?apiKey={{YOUR_API_KEY}}


Note: Ticket-Granting Tickets (TGTs) and Service Tickets are deprecated, but we will continue to support authentication using Ticket-Granting Tickets and Service Tickets until May 1, 2023.

Ticket-Granting Ticket and Service Ticket Documentation