PhysioNet
PhysioNet, run from MIT, publishes and preserves medical research data so that others can reproduce and build on it. Its holdings span physiological waveforms such as heart traces (ECG) and brain activity (EEG), structured clinical databases, imaging, and the software tools used to work with them.
It is the distribution home for several landmark datasets, including the MIMIC critical care databases, which makes it a good first stop when you are gathering clinical data for a RAG system. You can browse datasets by topic and download them directly from each dataset's page.
Licensing and access rules vary from one dataset to the next. Many are openly available, while others (particularly those with patient data) require you to become a credentialed user and sign a data-use agreement. Check the terms on each dataset before you rely on it.
Related sources
ClinicalTrials.gov
A US National Institutes of Health database of privately and publicly funded clinical studies. It holds structured records on more than 450,000 studies, including protocols, conditions, interventions, outcomes, and results, all in the public domain.
DrugBank
A freely accessible database that combines detailed drug data with drug target information, covering more than 15,000 drug entries. It links chemistry, pharmacology, and biology in one place, which makes it a strong knowledge source for medical and pharmaceutical RAG.
MIMIC-III / MIMIC-IV
Freely accessible critical care databases with de-identified health data from more than 40,000 intensive care patients at Beth Israel Deaconess Medical Center. They include vital signs, lab results, medications, and clinical notes. Access needs credentialing and a data-use agreement.
UniProt
A resource for protein sequence and functional information, with more than 250 million protein sequences and rich annotations. It is a core reference for bioinformatics, so it grounds life sciences RAG systems in reliable protein facts.