02.10.2013

The Food and Drug Administration (FDA) has announced that it will rescind approval for three of the four arsenic drugs that had been used in animal feeds at the request of the companies that market them.
The companies, Zoetis and Fleming Labs, already had largely withdrawn the three drugs from the market. The compounds are: roxarsone, carbarsone and arsanilic acid. Pfizer (Zoetis) withdrew its roxarsone drug, 3-Nitro, from the market in 2011. The product is no longer manufactured or used. Nitarsone, the last of the four drugs the groups, is the only known treatment for blackhead, or histomoniasis, a disease of turkeys.