Traditional medicines from plants, animals, and fungi contain chemical compounds that can interact with specific proteins in our cells called G protein-coupled receptors (GPCRs). These receptors control many important body functions and are targeted by about one-third of all FDA-approved medications. This review explains how scientists are discovering new therapeutic compounds from traditional medicines by systematically screening them against the complete library of human GPCRs, using advanced techniques to identify which compounds bind to which receptors. Famous examples include morphine from poppies for pain relief and compounds from ginseng that help regulate blood sugar.