Each source keeps its own record type and its official link. A shared medical vocabulary ties them together, so "heart attack" also finds myocardial infarction in every source at once.
SourceWhat it holdsRecordsRefresh
FDA MAUDEMedical device adverse-event reports26,557,997monthly
FDA FAERSDrug and biologic adverse-event reports20,588,503quarterly
ClinicalTrials.govRegistered clinical studies~600,000daily
DailyMedCurrent drug labels (SPL)~160,000daily
openFDA SPLStructured product labeling~262,000weekly
FDA recallsEnforcement reports, Class I–III104,594daily
ChEMBLCompound bioactivity (EMBL-EBI)~2,900,000per release
PubChemDrug substances (NCBI)4,634per release
RCSB PDBExperimental protein structures~260,700weekly