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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,{{YOUR_API_KEY}}

We also offer an endpoint for validating API keys. If you have developed an application that integrates UMLS data and you need to determine whether a user is a UMLS licensee, you can use this endpoint to validate the user’s API key.

Make a request that includes both your API key (validatorApiKey) and the API key of the user of your application (apiKey). For example:

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