I use the Frontline for fleas & heartworms he told me to use something like baby shampoo for bathing. He said regular shampoo/Dawn will kill the Frontline. And I use it every month and she's an inside dog and sleeps in my bed and I've never seen a flea on her. When I first got her (rescued) she was covered in fleas and sore spots caused from scratching. Has almost no hair on her belly so I can really see if a pest was there.