We bought this for our lab mix and it doesn't work.  Our dog is given a bath every week and for the most part is an indoor dog and she is scratching all over from fleas and we have even picked ticks off of her.

If you do decide to try it hold onto your receipt.  I called the 800 number and once I send in the receipt I will be given a full refund.  They do offer a money back gaurantee but they don't advertise it.