In treatment of balantidiosis of pigs, oxytetracycline was found to be 70% effective (Mwamba and Pandey, 1977), furazolidine 86.9% effective (Ver- hulst and Kifuka, 1975) and niridazole 89.3 % effective (Verhulst and Cor- net, 1975). Data from the present trials show that acetarsol is more effica- cious than oxytetracycline and equally efficacious as furazolidine. When ace- tarsol and oxytetracycline were administered simultaneously the recovery rate was found to be 100%.