The biggest reason fleas come back is because the home/environment the pet is in hasn’t been cleared of them. To fully rid the home of fleas and flea eggs, means vacuuming every room that your pet goes into. It’s very important to remember to vacuum the sofa, including all nooks and crannies, and in between floorboards, as flea eggs can fall off your pet’s coat and contaminate the environment. Bedding needs to be washed at a very high temperature or thrown out. There are some household sprays available in veterinary clinics that will treat any eggs in the home, if vacuuming hasn’t resolved the problem. The veterinary clinic where you buy the spray will advise you on how to use the product you buy.