Fladazole is used to treat vaginal infections caused by bacteria and is only used in cases of infections caused by bacteria. These are some of the cases in which Fladazole is used: urethritis and vaginitis caused by Trichomonas vaginalis. Intestinal amebiasis. Hepatic amebiasis. Giardiasis. Fladazole is used as a broad-spectrum antiparasitic and urethritis and vaginitis.