AS a dog groomer forget the sentry shampoo. first if they are on the dog they are in your house! So you have to treat the dog and house at the same time. Your vet will have a spot on treatment that you can use on your pup. It will cost more than what you can buy in the store but it will work and be safe for him. Before using the spot on I would suggest taking him to a good grooming salon for a bath while you treat the house with a good flea product that not only kills fleas but their eggs too. Too many flea baths are not good they can dry the coat out and he will itch anywaY, HOPE THIS HELPS.