Application Program Interfaces (APIs) are available to users to retrieve data from several drug information sources, including RxNorm, MED-RT and RxTerms. Currently there are six APIs available:

APIs are available as RESTful web services. A RESTful web service is a web service implemented using HTTP and the principles of Representative State Transfer (REST). The RESTful web services can return the data in XML or JSON. (SOAP access to the APIs is deprecated as of July 2019 and will be terminated in January 2020.)

We invite you to develop computer and mobile applications using National Library of Medicine (NLM) resources. We request that any application that makes use of NLM data include the following statement:

"This product uses publicly available data from the U.S. National Library of Medicine (NLM), National Institutes of Health, Department of Health and Human Services; NLM is not responsible for the product and does not endorse or recommend this or any other product."