I purchased hartz one spot at my local petsmart, not because of lack of funds but of convenience. Not a good choice. I have two beautiful cats I rescued about 10 months ago. They have been spoiled since they have been with me. They are a mother and daughter. I named them Mama and Rosie. I put Hartz on them. It should be renamed HURTS because that is exactly what it does not only to your trusting friend but to you. Rosie began to react within a few moments, as described by so many others. It was like she had rabies, running around clawing to get out, crying, then collapsing on the floor,then jumping. It was the most helpless, horrible feeling. I feel like an ass that I did not know this poison was on the market. I usually go to my vet but circumstance had me buy this #!#!! shit. I called my local 24hr pet hospital and they told me to wash her down right away. I used dawn and I also used johnson baby shampoo. I was told to watch her for 24 hrs to see if she foamed at the mouth, vomitted or started to twitch because she could start to seizure. I ask again to everyone why this F#!!&%#! product is on the market. What can we do. We can tell our sad stories but we need to make someone DO something. My girls are ok. I washed the again today. They are eating, playing and less lethargic. Thank the Madonna they are ok. I am going to look into our canadian laws. I went to my petsmart and talked to the manager I will follow up with written complaint and tomorrow I am going to call Hartz. We need to get Michael Moore to do a documentary on this!! Perhaps if enough people contact him it could be done. So in our grass roots way we need to tell everyone not to use this on their animals, we are their humans and we need to protect them. Keep the faith and my heart goes out to all of you who do not have your companions with you any longer.