Domiphen is a quaternary ammonium compound and cationic surfactant with antimicrobial activity.{53601,53602} It is active against A. viscosus, A. naeslundii, S. mutans, E. coli, and L. monocytogenes bacteria and inhibits C. neoformans yeast growth and spore germination.{53601,53602,53603,53604} It also inhibits the human-ether-a-go-go-related gene (hERG) channel (IC50 = 1.5 ?M in a whole-cell patch-clamp assay).{53605} Formulations containing domiphen have been used as antiseptics, disinfectants, and biocides in industrial, agricultural, veterinary, and clinical applications.