Triclabendazole sulfoxide- 13 C,d 3 is the 13 C- and deuterium labeled Triclabendazole sulfoxide. Triclabendazole sulfoxide (TCBZ-SO) is the main plasma metabolite of Triclabendazole, and exhibits anti-parasite effects. Triclabendazole sulfoxide can inhibit membrane transporter ABCG2/BCRP.