I found this site while searching for infomation about the drops. I’ve used them on both of my cats this week. The directions said continue use for seven days, but I only have done two applications in three days and will discontinue use Immediately. I KNEW this reaction wasn’t normal. The reason I’d been searching is that the younger cat has been vomiting after meals and can’t seem to keep anything down and the older cat just plain hates me now, is acting uncomfortable in general and feels quite warm. I’m making an appointment with our vet TODAY. Hartz sucks. Hey, thanks, Hartz. Whatta pal.