Hey there,
I use the Brewer's Garlic Yeast tablets for Brody. They were recommended by a breeder and seem to be working. I give him 1 tab a day. It is supposed to also help with coat and smell. It really seems to be working for the fleas. You can get the tablet at Petmart. For our little guys you give 1 full tab a day for pets as young as 4 months.
Hope this helps!