I have used topical flea products on both cats and dogs and never had any problems with them until today. I put Sergeants Gold on my dog this morning and by afternoon she was in a terrible state. She was itching, drooling, and scooting around all over the ground. I called the vet and they told me to give her a really good bath. They also told me something I didn’t know. They said they had seen dogs with reactions as severe as seizures to the Sergeants products. Hopefully, an allergic skin reaction is all my pet has had. I am not sure about using any of these products now, whether it be Hartz, Sergeants etc. Our dog Sweetie is a part of our family as are most pet owners pets. I hope this information has helped someone.