You might want to look at some of our products to help the skin. DERMA-IONX which is an oral homeopathic product stimulates the enzyme systems in the body which aids the skin to heal and helps with assimilation of nutritional components in diet and supplements. The supplements I use along with it include probiotics and Omega 3,6,9. These supplements together with DERMA-IONX can produce a synergistic response. I would also suggest that you give your dog only filtered water for drinking and bathing if your water contains chlorine or fluoride. You are trying to increase the numbers of the beneficial bacteria in the body to counter the yeast.
For the dietary modifications you might want to try a grain free diet with feeding cooling foods according to Chinese food therapy. Fish and turkey are considered to be cooling. Chicken and lamb are warming. Of course if your dog has a food sensitivity do not give that food.
Please feel free to contact us again if you have any other questions.