We all have problems with fleas on our pets and I have finally found a product that works! When our dog got sick a few months ago, we took him into the vet. She found that even though it was still the middle of winter (snow on the ground and everything!) He had a huge problem with fleas (not what was making him sick though.) She recommended we try to get the fleas under control as soon as possible and recommended giving him a small pill called Comfortis. Comfortis is FDA approved for flea control and is a phenomenol product! Within about a week of having given the dog the flea control, he was nearly flea free. Every once in a while we will find a few fleas on him but he is not scratching nearly as badly as he was before.
There are different doses of Comfortis for different sized dogs; bigger dogs are more expensive. The medication is available by prescription only but I recommend spending the extra money to get your dog to a vet to get this medicine. We now have two of the four dogs on Comfortis and the two who are taking it do not have any problems with fleas. We are planning on getting the others to the vet to get their medicine too.
It is more cost effective to buy a years worth of pills at one time since most vets (at least around here) will give you a discount on such a large purchase. Each pill is effective for one month and then they will need another dose. The pills are supposed to be beef flavored but our dogs don't like taking them. We have to put it in the back of their throats and hold their mouth shut long enough they have to swallow. (I don't like "flavored" medicine either, i don't blame them a bit).
Our vet told us that she has found the topical medications do not work nearly as well because the dogs rub them off when they are outside and since Comfortis is a pill instead of topical medication, it affects the fleas as they try to bite the dog. Your dog will probably still be quite itchy in the beginning but will soon be virtually flea free.