Biomedical and health data covers the science and practice of medicine: research literature, drug and protein databases, clinical records, and the results of clinical trials. It matters for a RAG (Retrieval-Augmented Generation) system because medical questions demand precise, well sourced answers, and this is where the primary evidence lives. A system grounded in curated biomedical data can cite a drug interaction or a trial result rather than guessing, which is exactly the assurance this field needs.
The dividing line here is between open reference data and restricted clinical data. Literature, drug databases, and protein libraries are broadly open and easy to start with. Real patient records, by contrast, are sensitive, so the datasets that contain them are protected: many require credentialing, meaning you complete ethics training and sign a data use agreement before you get access. Decide early whether your use case genuinely needs patient-level data, because the open reference sources cover a great deal without that hurdle.
Two cautions. First, licensing is uneven: some widely used databases are free for research but restrict commercial use, so check the terms before building a product on them. Second, accuracy carries real stakes here. Medical information ages, dosages and guidance change, and a confident wrong answer can cause harm, so favour authoritative, dated sources and make provenance visible to your users.
The sources below range from open drug and protein databases to credentialed clinical records and trial registries.