I've just seen th Sensitivy to Stronghold thread started by Mark and would like to expand on one of the comments from Liz.
I recently attended a lecture by a leading UK poisons expert from the Veterinary Poisons Service who advise the veterinary profession amongst other profesional bodies. It rather staggered me that the number1 reported poison that kills our cats were owners is Permethrin. As an aside but not relative to this thread - paracetemol is high on the list. The mind boggles as anyone who gives paracetemol to thei cats should be shot oor be certified,
The really annoying thing is that it simply needn't happen with simple knowledge and care. The continual source of this poison is owners applying Frontline for dogs to their cats thinking it was exactly the same as Frontline for Cats. It is not. Frontline for Dogs includes the active ingredient of Permethrin which can be fatal for cats.
Whilst I know it wasn't applied to the cats in Liz's story, there are lessons there for all. Whilst Permethrin is not present in Frontline for Cats, you should follow the manufacturers advice and keep cats separate until the liquid has had time to dry on them. From memory I believe they talk about an hour but this a minimum rule of thumb and I prefer 2 hours to be safe. The reason is that cats who are of the same family or close may lick each other and get the liquid in their system, which can cause problems.
In the case of cat and dog families, as a matter of course I would also keep them separate when applying Frontline for Dogs or similar treatment. Whilst Permethrin is not fatal to dogs it can be to cats if they lick the Frontline on the dog(s).
At one time the aforementioned flea treatments were only available on prescription from your vet. Whilst it is welcome that it has now opened up to chemists, etc, from a cost point of view, it is perhaps even more important to be alert to the dangers. My post is prompted by a local chemist selling Frontline and freely admitting that he didn't know the difference about dog and cat versions or anything about the Permethrinactive ingredient problem for cats. He said that he may refer any questions to the pet supply shop. That is simply frightening but not born out of ignorance. It is, in his case, born out of not caring about animals, not having sufficient penalties for wrong advice (as with human beings) and the lure of the £ sign. Needless to say I shall be monitoring him.