Hmmm? Good one, I know couple of things about pet meds having two little monsters (85 and 75lbs) getting script from the vet and having it filled from wallyworld is a whole lot cheaper. LadyHK gets fish meds off the net for human consumption. Doses are done by weight, if you look at what the vet gives your pet, cross ref them on the net. See how they compare. Meds have name brands, chemical and generic names. By knowing what the vet is giving your pet and cross ref'ing I think you can come up with what is comparable for the critters. Then it comes to weights and doses allergies and what nots. I hope this helps.