After reading the stories posted on this website, I realize I am one of the lucky ones. My two cats merely have a skin irritation that looks like a chemical burn at the application site. I washed the cats with soap and water the day after I put the flea drops on. Later, at my vet’s recommendation, I washed them again with dish soap. Their skin is still irritated from the harsh dish soap, and I hope they heal soon from the burns. I wanted to share this story to point out that these are inappropriately strong chemicals even when your pet is lucky enough not to have the nervous system reaction. The chemical burn, the two washings, the harsh dish soap, and the trip to the vet have been unnecessary trauma for them.