An oral treatment works quickly and is effective. Then I'd recommend a flea killing shampoo like advanatage. There is also DIY remedies such as dawn dish soap.
Oatmeal shampoo from a pet store.
Hi Marie: One cheap and good thing is to wash your dog in Dawn dish soap. Get your dog all fuzzed up with suds, starting at it's head and working your way back to the tail, and let them stay on the dog for about 5 minutes. Then, rinse completely and dry. You will be fighting a losing battle if you don't get the fleas out of the house. Vacuum the house, going slowly, and vacuum thoroughly. Then, put the vacuum cleaner bag, or empty the tube, into a plastic bag, seal it completely and put it outside into the trash. If you don't get rid of it, the fleas will crawl out. Also, you can make a spray of about 1/4 teaspoon of Dawn and a quart of water. Spray the areas that fleas live. It will take about a month (sorry) to break the cycle and kill all of the fleas, no matter what you use. Then, get some Frontline flea drops for the back of your dogs neck. Those you put on once a month. I get mine from https://www.vetsupplysource.com/. They're the cheapest and the stuff comes pretty quickly. Good luck
The best product is the flea pill the vets sell. Once you kill the indoor fleas and dip the pet, the pill is the best .
Marie...Your vet can give prescribe pills that will work very well but they are a little expensive but well worth it.