rxref - Tidy Utilities for 'RxNorm' and NDC Resolution

Provides a tidy, vectorized interface to the 'RxNorm' / 'RxNav' API for resolving drug names, 'RxNorm' Concept Unique Identifiers (RxCUIs), National Drug Codes (NDCs), and related drug concept metadata. The package supports workflows for mapping between drug names, RxCUIs, NDCs, ingredients, products, drug classes, and related concepts using data from the U.S. National Library of Medicine's 'RxNav' services <https://lhncbc.nlm.nih.gov/RxNav/APIs/> and 'RxNorm' <https://www.nlm.nih.gov/research/umls/rxnorm/>.