My cousin gave me some Frontline to use on my cat. He has had some fleas on him, but not bad, but he reacts like a maniac when one bites him and I can't stand to see an animal scratch themselves repeatedly, so put the frontline on him. three days later he was scratching again, but I thought it was just a mosquito bite or something, so two weeks later I notice there is a flea on my bed... just one. then two days later another flea, then a week after that fleas on the floor! Now I have a flea infestation in the house. I put out the tray of water with dish soap and have caught and killed about two dozen so far and am noticing less and less of them. they only bite me IN the house, not on the porch or in the yard!!! Very odd. So.... a friend recommended diatomaceous earth, but I have yet to find any in the health food store, pet store or department or home repair shops. Have you tried it? Does it work like they say? Is it very expensive? Why couldn't I just grind up old sea shells or pick up sand from the seashore and put it down? My cousin gave me a capstar to use, but had to toss it in the cat's mouth as he would not unclamp his jaws, so not sure if it stayed in there or not! I also bought some clove and peppermint flea spray and tried it on an ant mound by the back porch and it killed them dead, so plan to use that on the cat too and see if it helps, but did not want to put that and the frontline on at the same time.