Triclabendazole (commercial name Fasinex) is a member of the Benzimidazole family of anthelmintics. The benzimidazole drugs share a common molecular structure, triclabendazole being the exception in having a chlorinated benzene ring but no carbamate group.

Triclabendazole displays high efficacy against both immature and adult liver fluke.

It is generally accepted that benzimidazoles like triclabendazole bind to beta-tubulin and prevent the polymerisation of the microtubules of which they are part.