I wanted to add our story because the same ingredients in a different Hartz product (carpet treatment) made our cat seriously ill.
One of our cats turned out to be extremely sensitive to the pesticides in the Hartz 3 in 1 carpet treatment, resulting in a weekend stay at the veterinary emergency room. The telltale symptom was that his third eyelids came up and didn’t go back down–at the time we took him in to the vetER, we didn’t realize at the time how serious his condition would become, so it was fortunate we were already there when he began to have tremors and needed to have oxygen, medication, and fluids administered, the last to flush the pestidices out of his system. (We thought the third eyelids were inflamed conjunctiva, and had taken him in for that, but the vet recognized the symptoms of pesticide poisoning right away.) I came across this site when I got back home and was looking up the ingredients of the Hartz product to pass along to the vet to confirm her diagnosis, since I’d thrown away the packaging. Oleo’s exposure to the medicine had to be minimal–he may have gotten some that we missed with the vacuum on his paws that he then licked off, or he may have ended up breathing in some of the dust, although we’d taken the precaution of isolating the cats on the screened back porch while dusting the house. It dismays me that we could have killed our cat by using a product we thought we could trust…and the irony is that we still have the fleas. I continue to vacuum every day to mechanically control the fleas, and I continue to take the precaution of putting the cats out on the porch each time I vacuum in case any residual powder is stirred up. Oleo’s on a slow road to recovery. I hope our story can help someone else avoid what we went through, or worse.