Here are 40k+ NDCs
- they exist in OHDSI Athena
- RxNav has record of some/most of them (even though the relationship between NDC and RXCUI “isn’t maintained by NLM”) - screenshot below
- via RxNav, it appears that MTHSPL is the source (DailyMed SPL info stored in RxNorm), but i don’t see them in the rxnsat table of the RxNorm data like other MTHSPL NDCs
- generally, you also won’t be able to find them by searching NDC in DailyMed
- also - they are NOT in RxNorm historical NDCs as accessed via the API
- also they are not in any of the current FDA data files
Within Athena, where do these NDCs come from? Are they from some other source I’m not aware of? Are they user contributions over time? Are they from archived versions of DailyMed SPLs? Any clues would be greatly appreciated! Thank you!