I have a poodle that was healthy and well taken care of. After the 2nd dose of hartz topical flea my 9 year old dog is fighting for his life. It is experiencing muscle spasms and is barely able to walk. Neither the vet or I couldn’t figure out what went wrong. It never had any of this behavior and it just started to get really bad very fast. I bet this topical flea poison did damage to its nerve system. I hope its not permanent and it can survive. It can’t be so many pets are allergic to its components as i’ve read. Take this OUT of the MARKET!