We found a few fleas on my dog and decided to put the drops on her. We had used it before and had no problems. So we put it on her and she stops itching. The next morning, she wakes up with a limps we didn’t really think anything about it, we just thought she slept weird or something. It didn’t hurt to the touch so we just put some ice on it and let her walk it off. The next day, I wake up and she can barely walk at all and whenever I would touch her arm, she would wince. We wrapped it up and put more ice on it and carried her everywhere. The next morning, I woke up to the sound of her SCREAMING in pain. She refused to put any weight on it and every time she would take a step, she would collapse. At this point, we were extremely worried and decided to do some research. I read about the hartz poisoning but I didn’t really see much about limping or extreme leg pain. So we called a vet and they said to give her a bath and remove the drops to see if that would help. Immediately after we bathed her, she perked up and could walk a little bit better. She still had a little bit of a limp, but you could tell she was doing way better. I will never use that medication again because I never want my dog to be poisoned like that again. PLEASE DONT USE THIS PRODUCT!