The quinoline derivative diiodohydroxyquinoline (INN) or iodoquinol (USAN), one of the halogenated 8-quinolinols widely used as an intestinal antiseptic, especially as an antiamebic agent. Iodoquinol is also used topically in other infections and may cause CNS and eye damage. It was discovered by Adco Co. and introduced as diiodohydroxyquinoline. The mechanism of action is unknown. Iodoquinol acts against the trophozoites of Entamoeba histolytica. Iodoquinol produces its amebicidal effect at the site of infection, since it is poorly absorbed from the gastrointestinal tract and can reach high concentrations in the intestinal lumen.