Last year when we bought our house, it had fleas. Since we had 2 ferrets at the time, we had to be careful as to what we used. The Vet told us to sprinkle our carpets with salt, just plain table salt. He said to cover the floor evenly and let it stand there all day and over night if it did not bother us. Then vacumm it up. He said the salt will dehydrate the flea and if any hatched out in the bag, the salt would dehydrate them also. If any eggs remain in the carpet the salt left behind will dehydrate them, as well. This is all that we used and we have had no fleas since.