I bought a bottle of brewers yeast at walmart for flea control as I read somewhere it might help.
It made my german shepherd so sick and he got an ear infection right away. I had to take him to the vets to get meds. The vet would not give me oral antibiotics, but gave me ear drops. I wish I had bought fish antibiotics and looked up the dosage from revival animal health or drs foster and smith for him. He ended up biting me really badly because he didnt want the drops put in his ear and I ignored the threat display to get them in his ear and he attacked me...not that it was his fault..he is a wolf hybrid german shepherd and he has a large set of teeth.
Never use brewers yeast for flea control it doesnt work and it causes illness.
ON the contrary, I have a big steel pot I use for all my animals water and every time I fill it up I put a cap ful of apple cider vinegar in it, the best kind is the kind at the health food store but I just use the kind at the dollar store, and it starts working in about two weeks. They dont even notice it is there and it cuts the yeast out of their bodies and the fleas dont really like the taste of it and I also mop with it and I love it for all it does!