I noticed a few fleas in the house and fleas on my cats, so I went to to Petland, a NYC chain pet store, to get flea collars for them. They advised me to use Hartz advanced Care Flea & Tick drops Plus+ 4 in 1. I bought two sets and yesterday evening went to the Hartz website to read the instructions for application carefully, and watched the application video. I then applied the product as described. The instructions for applications led me to believe that it would be a drop of liquid that would be applied to their skin through the parted fur, but there was so much liquid in the vial that it spread all over the back of their necks.
My 5 yr old cats were upset at the product on their fur and immediately started scratching it off with their hind legs and then licking their feet clean. As the evening wore on, they became more and more disturbed. I noticed that they had begun to groom each other to get rid of the stuff, which meant they were ingesting it. I was already concerned but decided to wait until morning to see if there were bad reactions. By morning they were still sleeping when I got up. Then they started stumbling around crying, their heads were bobbing, and they were suffering confusion. We took them to the vet and he said he sees about three cases a week of such adverse reactions. They will be hospitalized for three days on IVs and being treated for trauma and tested for other horrible reactions.