The interactome of arzanol was investigated by MS-based chemical proteomics, a pioneering technology for small molecules target discovery. Brain glycogen phosphorylase (bGP), a key regulator of glucose metabolism so far refractory to small molecule modulation, was identified as the main high-affinity target of arzanol. Competitive affinity-based proteomics, DARTS, molecular docking, and in vitro biological assays provided molecular mechanistic insights on the arzanol-enzyme interaction, qualifying this positive modulator of bGP for further studies in the realm of neurodegeneration and cancer.