Searching Google for Seresto Flea collars for cats I came across this posting back in 2012. I sympathise with the cat owners and hope that their two cats recovered from their allergic reation to Seresto. My own cat suffers a huge allergic reaction to flea bites, which results in constant scratching of his back, the fur becoming coarse and falling out, and extensive scabbing. We tried all of the proprietory flea treatments but without any real success. Then in 2008 we moved to France and during one of his flare ups we took him to a local vet, who recommended a Seresto Flea Collar. Since that day he has had no further problems and is not bothered by the wearing oif the collar. I noted a further post whci recommended never, never, never put a flea collar on a cat. I am convinced that this collar, replaced every 6 - 8 months has saved my 21 year old cat from a life of misery.