Fenbendazole (FBZ) is a broad-spectrum benzimidazole anthelmintic drug used in veterinary medicine for over 40 years. Originally developed to treat parasitic worm infections in animals, it has attracted growing scientific attention due to its interactions with fundamental cellular mechanisms. This guide summarises peer-reviewed research — including studies from Yale University, NIH-indexed journals, and recent pharmacokinetic modelling — with the goal of presenting what is ac