RxNorm is a name of a US-specific terminology in medicine that contains all medications available on US market. It can also be used in personal health records applications. It is part of UMLS terminology and is maintained by the National Library of Medicine.
Use
RxNorm offers an API that is called RxMix and that offers functions to detect RxNorm concepts in input strings.
References
RxNorm Wikipedia(Text) CC BY-SA