Our steer had no side effects from the Griseofulvin (spelling may not be right). And we tried EVERYTHING prior to that (shampoos, topical ointments, sprays, etc.). He continued to eat and gain well for him (he has been a picky eater from day one). Our vet also said we could take Captan (a plant fungicide that you can get at most any greenhouse) and melt a jar of vaseline and mix as much Captan in as we could, let it solidify and smear it all over - but we didn't need to go that route because of the Griseofulvin clearing it up so well. I know if anything in the future shows any hint of ringworm we will be getting more Griseofulvin right away. Hope it works for you.