We almost lost our beloved Oz after using this horrible medicine. This is our first pet, a beautiful male cat that we have both fallen in love with. After dealing with fleas, I decided a trip to the vet was too costly, and buying over the counter medicine should work. I put the Hartz flea control on him and the next day he was very lethargic and constantly wanted my attention. I did not like how he was acting so the very next day (day 2 of medicine) I took him to the vet who said that this medicine is known to kill cats. They ended up having to sedate him to take care of his problem through medicine and a bath. Since Oz was a 1 year old the vet said he was young and had a strong will to live….which is probably what kept him alive. What is there to do now? Contact Hartz? Spread the word? I just found this site, and I would love to be an advocate to stop the use of Hartz. What can I do? What will Hartz do for the loss of animals?