drugref.org is a public-good drug-information service: a registry of active drug moieties, each with an immortal identity and transparent, append-only links to the world's open drug vocabularies. Any EHR, pharmacy system, prescribing tool or research pipeline can consume it on equal footing — free software, free data, reproducible from source.
Reliable drug reference data — what a substance is, how it is classified, what it interacts with — sits behind proprietary licences in most of the world. That locks safe prescribing support to whoever can pay, and locks health-IT projects into vendors. drugref.org takes the opposite stance: the identity and knowledge layer of medicines is a commons, built entirely from public-domain and openly licensed sources, and published under a licence that keeps it open for everyone, forever.
This is a resuscitation of the original drugref.org project, rebuilt from the ground up as drugref v2 with modern identifiers, reproducible ingestion, and a design hardened for decades of use.
Every active drug moiety gets a stable UUID that never changes and is never reused — minted deterministically, so independent installations agree on identity without coordination.
Append-only, auditable links from each moiety to UNII, InChIKey, CAS, ChEBI, RxNorm and more. Corrections supersede — they never silently overwrite history.
Source-neutral drug class registry populated from MED-RT (mechanism of action, physiologic effect) and MeSH pharmacologic actions.
Class-level contraindication data from MED-RT, expanded to candidate drug–drug pairs — the advisory foundation for interaction checking, clearly tiered by evidence.
Two tiers are planned: the global tier (jurisdiction-independent substance identity, chemistry, classes, interactions — being built first, in this repository) and a later local tier for country-specific packaging, product and subsidy data.
Every fact in drugref traces to a public-domain or openly licensed upstream release, and the entire database can be rebuilt from those sources by anyone:
Licensing is a hard rule, not an afterthought: only AGPL-compatible sources are ever bundled. Licence-encumbered national sources can attach to a local installation as separate plug-ins, but never contaminate the commons.
drugref.org is stewarded alongside the Cairn EHR project, but it is not a Cairn component. Cairn consumes drugref through the same public API offered to everyone — the steward has no privileged access. drugref data is advisory reference information: it informs clinical software, but no system is ever required to route its records through it.
The project is developed in the open at github.com/cairn-ehr/drugref — code, design specifications, roadmap and issues. Contributions are welcome: source-licence review, ingestion of additional open vocabularies, API design, and national local-tier pilots are all on the horizon.
All code is licensed AGPL-3.0; bundled reference data retains its upstream open licences (see the NOTICE file).