I really wish I would have found this site sooner! Jerry is a 6 year old overweight cat we adopted about 3 months ago. He is extremely playful and full of life, up until about 5 days ago. We applied Hartz to Jerry as directed Thursday night. Friday he seemed a bit out of it and tired, but still up and about. Saturday he did’t really come out of the room too much and didn’t seem interested in treat…but he would still eat them. Sunday I started noticing he wouldn’t eat his food. This made me a bit concerned, but cat get finicky sometimes. Monday night he wasn’t drinking water, but what was worse is that he would stand by the bowl and not drink anything. Tuesday early morning we took him in for diagnosis. He was running a fever and was dehydrated. They pumped him full of fluids and sent us on our way. All night Tuesday he was vomitting, and Wednesday morning he was vomitting blood. So this morning we took him in only to have the vet tell us he is still running a fever and now has signs of jaundice. The vet let us know NEVER to us Hartz because of the adverse effects like these. Now Jerry is in the hospital getting bloodwork done and has to stay over night. Luckily the vet is really flexible, because all these visits now cost $650. I will update as soon as he gets out. Yet one more customer of Hartz.