I'm very interested in learning what the difference is between eprinex and ivermectin. I've had to look extensively to dig up some definitive information so thought it was worth sharing. After some extensive searching, I came across this site in my research: http://www.jefferslivestock.com/eprinex … /cp/17185/ which is where they sell ivomec eprinex pour on for cattle. They also sell ivomec ivermectin pour on for cattle: http://www.jefferspet.com/ivomec-pour-on/p/17186/ If you read the descriptions of the two drugs in terms of how they work, they're pretty much identical, it seems. http://www.jefferspet.com/images/label/17186.htm http://www.jefferspet.com/images/label/17185.htm Ivomec Eprinex contains Eprinomectin and Ivomec Ivermectin contains ivermectin. Their mode of action seems to be identical, as is the dosing. It seems Eprinex kills more than the ivermectin does. It says here that eprinex is "the broadest-spectrum parasite control product available. Only EPRINEX kills 42 species and stages of internal and external parasites, including roundworms, lungworms, grubs, mange mites, horn flies, and biting and sucking lice." Ivermectin pour on has a 48 day withdrawal period for cattle, while Eprinex has a a zero withdrawal recommendation for cattle. That's quite a significant difference that seems is worth considering for poultry as well, though they're off label use for poultry to begin with. So, is it safe to say then that Eprinex (versus ivermectin) is the better choice for poultry, for mites/lice/deworming? I thought I should raise this question as it really is not clear what the difference is when I read the various poultry forum postings, and the information seems a bit hard to find.