Some anti-flea products for dogs that have to be given on the skin are highly toxic for cats. Because it contains permethrin and insecticide. This material/substance belongs to the pyrethroids which are very toxic to cats. It’s that toxic that not all cats might survive.
Permethrin – Wikipedia
Permethrin is a common synthetic chemical, widely used as an insecticide, acaricide, and insect repellent.
Pyrethroids – Wikipedia
A pyrethroid is an organic compound similar to the natural pyrethrins produced by the flowers of pyrethrums (Chrysanthemum cinerariaefolium and C. coccineum). Pyrethroids now constitute the majority of commercial household insecticides.
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