RxNorm Lookup

What is RxNorm?

RxNorm is a standard clinical drug vocabulary developed and maintained by the National Library of Medicine (NLM). Compared to NDCs, RxNorm is a normalized naming system for generic and branded drugs. NDCs might have multiple numbers assigned for the same drug because there is usually more than one manufacturer for the same medication, while RxNorm assigns a unique concept identifier or RxCUI to define the same drug regardless of manufacturer.