I use a Neem shampoo weekly for my guys and brewers yeast with garlic tabs. We had been using the vet topical solutions and every single one has not worked. I think fleas are just so bad here this year that nothing is working. We're retreating our home and yard over the weekend and bathing the babies at work as well. Start fresh. It's my last resort, but Adams Flea & Tick PLUS mist has been my savior. I hate to use chemicals, but it's the only thing keeping fleas off this year.