My wife bought Hartz Ultraguard at Walmart and applied it to our one year old cat. Five minutes after application, our cat began running around the house panicking and meowing very loudly. She began hiding and after I found her, she was panting as if she could not catch her breath. Additionally, one of her eyes appeared to be swollen. We called an emergency vet’s office and told them what we had used, and she told us to immediately wash it off her fur with Dawn dish detergent. She said this stuff is poisonous to cats and she’s seen multiple cats die as a result of having this applied. Just a warning to all: DO NOT USE THIS PRODUCT. It can kill your cat! If you’re reading this because you made the mistake of buying and applying it, wash it off your cat with dish detergent as soon as you can!