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UMLS API Technical Documentation

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

API Terms of Service

Automating UMLS Terminology Services Downloads

Download any RxNorm, SNOMED CT, or UMLS release using our download API.

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

Step 2: Find the URL for the file you want to download and send a request. Examples:

Download RxNorm Weekly Updates

https://uts-ws.nlm.nih.gov/download
?url=https://download.nlm.nih.gov/umls/kss/rxnorm/RxNorm_weekly_10052022.zip
&apiKey=YOUR_API_KEY

curl example:

curl "https://uts-ws.nlm.nih.gov/download?url=https://download.nlm.nih.gov/umls/kss/rxnorm/RxNorm_weekly_10052022.zip&apiKey=YOUR_API_KEY" -o RxNorm_weekly_10052022.zip

Download the US Edition of SNOMED CT

https://uts-ws.nlm.nih.gov/download
?url=https://download.nlm.nih.gov/mlb/utsauth/USExt/SnomedCT_USEditionRF2_PRODUCTION_20220901T120000Z.zip
&apiKey=YOUR_API_KEY

curl example:

curl "https://uts-ws.nlm.nih.gov/download?url=https://download.nlm.nih.gov/mlb/utsauth/USExt/SnomedCT_USEditionRF2_PRODUCTION_20220901T120000Z.zip&apiKey=YOUR_API_KEY" -o SnomedCT_USEditionRF2_PRODUCTION_20220901T120000Z.zip

Download the UMLS Release

https://uts-ws.nlm.nih.gov/download
?url=https://download.nlm.nih.gov/umls/kss/2022AA/umls-2022AA-full.zip
&apiKey=YOUR_API_KEY

curl example:

curl "https://uts-ws.nlm.nih.gov/download?url=https://download.nlm.nih.gov/umls/kss/2022AA/umls-2022AA-full.zip&apiKey=YOUR_API_KEY" -o umls-2022AA-full.zip