The NLM Drug Interaction API is gone — here's what to use instead

The National Library of Medicine discontinued the RxNav drug-drug interaction API on January 2, 2024, with no migration path or direct replacement.

RxNav still supports other functions like drug name normalization and RxCUI lookup, but apps using the interaction endpoint lost a key safety check.

The article recommends rebuilding interaction data from sources such as DDInter 2.0, openFDA, and the ONC High Priority list.

RxCheck is presented as the most compatible drop-in alternative for teams that need API-based drug interaction screening.