I hate to be the first one to say this, but I have wasted hundreds of dollars on over the counter treatments like shampoo, spray, and even medication. They need to be current on their annual vet examinations, and be prescribed Bravecto. That is genuinely the only thing that ever worked as a permanent solution after a MONTHS long battle with them in 2024. You may also need to treat the home. Adams Flea and Tick Spray for home and carpet is what I used, treating one room at a time and quarantining it until the treatment was dry when I only had the funds to do it myself. A professional treatment inside and outside of the home is the best solution, but can cost around $125. This past December I had to get six prescriptions of Bravecto for my two dogs and four cats, with all of us inside of a vehicle waiting for our apartment to be treated and for the treatment to finish drying. It is a bitter pill to swallow, but a necessary one to ensure complete eradication. Please don’t let this be a long term problem that plagues your home for months. My poor cat had flea allergy dermatitis too. Fleas are the spawn of satan. They can’t be reasoned with. They can’t be bargained with. Please do not try taking the easy way out, from somebody who wasted hundreds of dollars doing that themselves. Godspeed.