Is it safe to treat your cat with your dog's flea treatment?
The safest answer is no. We strongly recommend to carefully read the instructions of any product you intend to apply to your pet, as many supermarket dog flea treatments are extremely toxic to cats. These treatments can contain permethrin, which is toxic to cats. Permethrin poisoning causes ataxia, tremors, tachycardia, salivation, dilated pupils and seizures, which can be fatal. Effects start between 1-12 hours after exposure and last up to 3 days.
The only treatment is supportive care. It is also worthwhile mentioning that dog parasite control products which do not contain permethrin can also cause problems when applied to cats. Concentration of the formula and dose sizes differ amongst products, so if you are going to apply anything on your cat, please use products intended for cats.
At the least, if you are going to purchase anything for your pet without professional advice, please read the instructions.