My dog for the first time ever starting breaking out in hives, we were unsure of what the cause might be until we went to the humane society with our cat, and was told by the vet that Hartz is a dangerous product. So when we arrived back home that day with the cat, my dogs face was so broke out with hives, I broke down in tears, she looked as though there was golf ball stuck on the side of her mouth, her eye was almost swollen shut, so we rushed her to the vet, the vet had also told us that we were lucky, she said that she has had some many animals come in with seizeor ( sorry I am horrible speller) because of using this product, because they put so many toxic chemicals in it. So it’s been a long fight to keep these hives off of her, but they don’t seem to being going away, the only thing that has helped for a short period of time is benderyall. I wish there was some way that I could make them go away for good, well all I know is that I WILL NEVER LET THAT PRODUCT IN MY HOME AGAIN!!!!!!!!