You can also use cornmeal they eat it and drink water and then they swell up and die.
Borex will also work well on fleas. If you have carpet in your house just sprinkle some on your carpet leave it for a few day. then Vacumn it up. It will freshing up the carpet and kill the fleas. Safe for you and your pets. If you don't want to try that
Diatomaceous Earth Food Grade. Work on every thing.