On Sunday I applied Hartz Flea and Tick drops to my almost 6 month old American Bulldog Diesel. Everything seemed fine. He was okay all day Monday and then Tuesday when I got up I took him out of his crate and he was covered in bumps. I started pulling back his fur (he is white) to see them better and saw that they looked like hives. My husband got up and said he would handle it to go on to work. I left, very worried. My husband called our vet and left a message for him to get back with us as soon as possible and he called the local animal hospital. The animal hospital told my husband to call the Hartz 1-800# . I called and the woamn I spoke with told me to wash him with dish liquid and rinse him throughly. My husband did that and the hives seemed to go down. In the meantime our vet called back and told us to give him an adult dose of Bendryl every 8 hours for the next 2 days then bring him in on Saturday or call him if it gets worse. So far that is all that has happened. I am very worried after reading this site that it will go further. I will post more if anything else happens.