Had a little chat with the local vet the other day and they never used navigator (nitazoxanide), but he said it was being discontinued, he didnt know why.
These are not for sale for humans and animals must have a vet order it.
But just wanted to clear up, as to why its off the market for horses with EPM.......it worked very well, I have seen several horses "cured" of this condition with the stuff, in CA.