RxNorm Code Set

Medications are query able in i2b2 using the RxNorm code set. We have chosen to use RxNorm over other medication code sets (such as NDC due) to its simpler nature, lower volatility, and more user-friendly methods of classification.

To construct the medication ontology you see in i2b2@UNC, we have created a custom ontology that presents RxNorm codes to a hierarchy defined in the National Drug File Referent Terminology (NDF-RT).

Additional information on the RxNorm code set in use at UNC and the system used to derive these relationships is available from the U.S. National Library of Medicine RxNorm website: www.nlm.nih.gov/research/umls/rxnorm/overview.html