The VSAC FHIR API can now retrieve expansions for intensionally (logically) defined value sets. You need to have a UMLS License and authenticate using your UMLS API Key.

Example: https://cts.nlm.nih.gov/fhir/ValueSet/2.16.840.1.113883.11.20.9.46/$expand

Find our documentation here: FHIR® Terminology Service for VSAC Resources.

Last Reviewed: February 22, 2021