There's a huge difference between using something off-label in a way that has decades of support behind it and using something that has never been researched in an animal. That's all I'm saying. I just did a one-minute search and found five universities (MSU, Kentucky, U Hawaii, Vermont, and NH) all giving owners specific directions TO use fenbendazole in poultry and exactly how to dose it. It's been studied in poultry for at least thirty years. There's a huge body of research that lays out exactly what it metabolizes into in chickens, how long those metabolites stay, and (this is key) what the acceptable residue is for eggs and meat. The USDA, in other words, knows perfectly well that it's being used in poultry. Heck, carbaryl (Sevin) isn't registered for use in poultry - even though its number-one use in the US is as a poultry miticide, it's used in all the commercial houses, and it's been studied since the 50s. Ivermectin, moxidectin, flubendazole, levamisole, hygromycin, pyrantel, on and on and on - good research, established doses, history of study in chickens. Eprinomectin - nothing. Studied very well in cows, fantastic in cows because they partition it from the milk. No research in chickens. Registering something for use in a commercial animal takes looooaaads of money, and for compounds that aren't either novel or expensive it's not worth it for the pharma companies to spend. Doesn't mean it hasn't been used or have veterinary support or Ag college support and extremely good data about efficacy and safety. I very much doubt that Eprinex residue in eggs or meat is going to hurt an average human, because an average human could take the bottle of Eprinex and swallow a teaspoon and it's not going to hurt them. Would worm them really well, but wouldn't make them sick. So I am sure you can use it and give it to your chickens at doses ranging from too small to gigantically too large and nobody's going to die. However, that doesn't mean there actually is a recommended dosage supported by research, OR that there is no withdrawal time for chickens. The no-withdrawal-time data has ONLY been studied in cows, which metabolize things differently because they're not birds. Saying "Eprinex should work - my dosage would be a guess, though" is completely fine and accurate. I'm just not sure it's a good idea to say to people on a message board who trust answers to be the right ones that 1) There's a known safe or effective dosage, or 2) There's no withdrawal time.