Researchers at UC San Diego and collaborators released the GNPS Drug Library, a publicly available MS/MS reference atlas of thousands of drugs, metabolites, and analogs to detect drug exposures directly from untargeted metabolomics data. The resource, described in Nature Communications, maps spectral fingerprints to pharmacologic classes, exposure sources and mechanisms to improve empirical exposure records beyond patient histories or medical charts. Separately, an online tool and related pipelines now enable clinicians and researchers to compare biological samples against such libraries to identify unreported prescription, over‑the‑counter, and environmental drug exposures. Developers argue these approaches can retroactively reconstruct exposure histories, informing pharmacology, toxicology, and clinical decision‑making where records are incomplete. The combination of shared reference libraries and web‑accessible analytic tools could change how drug exposure is documented in clinical and research settings, with implications for pharmacovigilance, drug‑interaction screening, and precision medicine.