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

API Terms of Service

Retrieving Source-Asserted Information

URIs | Query Parameters | Sample Output

URIs with /source/{source}/{id} support the following use cases:

Note that ‘current’ in the URI can always be used to search against the latest UMLS publication.
You may use any valid UMLS release back to 2008AA in your URI if you would like to search against a particular version of the UMLS.


The base URI is

Sample URI Description Returned JSON Object classType
/content/current/source/SNOMEDCT_US/9468002 Retrieves Source Concept SourceAtomCluster
/content/current/source/MSH/D015242 Retrieves Source Descriptor SourceAtomCluster
/content/current/source/LNC/54112-8 Retrieves Code SourceAtomCluster
/content/current/source/SNOMEDCT_US/9468002/atoms Retrieve atoms in a source-asserted identifier Atom
/content/current/source/SNOMEDCT_US/9468002/parents Retrieve immediate parents of a source-asserted identifier SourceAtomCluster
/content/current/source/SNOMEDCT_US/9468002/children Retrieve immediate children of source-asserted identifier SourceAtomCluster
/content/current/source/SNOMEDCT_US/9468002/ancestors Retrieve all ancestors of a source-asserted identifier SourceAtomCluster
/content/current/source/SNOMEDCT_US/9468002/descendants Retrieve all descendants of source-asserted identifier SourceAtomCluster
/content/current/source/SNOMEDCT_US/9468002/attributes Retrieves information about source-asserted attributes Attribute

Query Parameters

Parameter name Required? Y/N Description Valid Values Default value Usage Note
apiKey Y An API key is required for each call to the API. Visit your UTS profile to obtain your API key. n/a n/a n/a

Sample Output

Sample output for…

	"pageSize" : 25,
	"pageNumber" : 1,
	"pageCount" : 1,
	"result" : {
		"classType" : "SourceAtomCluster",
		"ui" : "9468002",
		"suppressible" : false,
		"obsolete" : false,
		"rootSource" : "SNOMEDCT_US",
		"atomCount" : 8,
		"cVMemberCount" : 0,
		"attributes" : "",
		"atoms" : "",
		"descendants" : "",
		"ancestors" : "",
		"parents" : "",
		"children" : "",
		"relations" : "",
		"definitions" : "NONE",
		"concepts" : "",
		"defaultPreferredAtom" : "",
		"name" : "Closed fracture of carpal bone"