Hartz Flea Spray nearly killed my cat

I am the proud owner of a beautiful black haired persian cat. His name is Buster and last night I nearly killed him because of Hartz Flea Spray. Buster is 3 years old and the most sweet natured cat. I noticed a couple of fleas on him the other day so went out and bought the Hartz flea spray. Last night I sprayed him as per the instructions and within hours he was foaming at the mouth, seizing. He could not stand nor even meow. He just looked up at me with these huge black eyes begging me to help him. I rang the emergancy vet and they told me to bath him immediately with soft soap and if he didn’t improve immediately to bring him in. They said that Hartz is a killer and to never use the products. Pity I didn’t know that 24 hours ago.  Luckily for me after the shower things seemed to be better. He was walking although a tad wobbly and meowing softly. By this morning he had improved although still tired. I can’t understand how a company can keep products on the market that are so harmful to the animals they are supposed to be aiding. It is a disgrace!