5-Hydroxymebendazole is the one metabolite of Benzimidazoles. Benzimidazoles are safe, broad-spectrum anthelmintic agents and are widely used for prevention and treatment of parasitic infections in food-producing animals.
References:
[1]. Hou XL, et al. Development and validation of an ultra high performance liquid chromatography tandem mass spectrometry method for simultaneous determination of sulfonamides, quinolones and benzimidazoles in bovine milk. J Chromatogr B Analyt Technol Biomed Life Sci. 2014;962:20‐29.