Antiprotozoal and antimicrobial agent used mainly in veterinary practice.
Arsanilic Acid
An arsenical which has been used as a feed additive for enteric conditions in pigs and poultry. It causes blindness and is ototoxic and nephrotoxic in animals.
Carbadox
An antibacterial agent that has been used in veterinary practice for treating swine dysentery and enteritis and for promoting growth. However, its use has been prohibited in the UK following reports of carcinogenicity and mutagenicity. (From Martindale, The Extra Pharmacopoeia, 30th ed, p125)