I put Hartz advanced flea drops on my beagle and my cat 2 nights ago. Since last night my cat has been acting very strange, agitated, and even paranoid. I took her to an emergency vet after looking at this web site. The vet said he didn’t see anything wrong with her, and the trip to the vet seemed to snap her out of it a little, but she is still acting crazy today. So to save a few bucks I used this product, and ended up spending $60 for a vet’s reassurance that she’s OK, which I still have my doubts about. And the most ironic thing is, the stuff doesn’t even work. I just picked 2 fleas off my dog today. Save your money and your pets’ sanity and buy the vet recommended flea products. This product is a sham and should not be allowed on the shelves.