We have had 2 cats for about a year now. I will admit I have been a bit crap about de-fleaing them (I have done it, used the drop things on the back of their necks twice and given them tablets a couple of times, but not every month or whatever it's supposed to be). Recently they started scratching a LOT, even though I had given them tablets only 2 weeks previously, and dp had bites on his ankle. I got a flea comb and combed masses out of them both - about 25 live ones on each of them. Freaked out, hoovered, sprayed, had all the sofa cushions off, the lot. Gave more tablets and drops on the advice of the pet shop lady. That was last week, and they seemed to have mostly stopped scratching, then today i have combed a couple more live ones out of both of them, much smaller ones admittedly, but shouldn't the drops stop them getting them? Or do they just keep them under control? Is this just normal when you have cats?