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

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.

You can find the API key in the UTS ‘My Profile’ area after signing in. An API key remains active as long as the associated UTS account is active.
To generate a new API key, click ‘Edit Profile’, select the ‘Generate new API Key’ checkbox, then scroll down and click ‘Save Profile’. Your new API key is now available for use.

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: AccessGUDID users can now use the API Key authentication method. For AccessGUDID users that have previously implemented Ticket-Granting Tickets and Service Tickets for authentication, please refer to this documentation:

Ticket-Granting Ticket and Service Ticket Documentation

UMLS API Technical Documentation

User Authentication

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

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

Note: AccessGUDID users can now use the API Key authentication method. For AccessGUDID users that have previously implemented Ticket-Granting Tickets and Service Tickets for authentication, please refer to this documentation: