Sunday night my mom applied the Hartz drops to my cats back. The next morning I went to check on the cat before I left for work and he was in the bedroom having a seizure and constantly twitching. I immediately took him to the vet and while i was waiting he had another seizure and after they took him back another one. They had to give him diazepam and some other medicine to control the twitching and seizures. He was over 10 lbs as the drops indicated. As soon as I took the cat in, he was in the kennel and the doctor looked at him and immediately asked had I applied the Hartz flea drops. He spent 1 full night at the vet and is home not but still doesn’t act like he is feeling well because his third eyelid is covering most of his eyes. Please no one use this stuff and let everyone you know, know about this.