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 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.
For the dietary modifications you might want to try a grain free diet and feeding cooling foods according to Chinese food therapy. Fish and turkey are considered to be cooling so would be better choices than chicken or lamb which are warming. Of course if your dog has a food sensitivity to a particular food do not give that food.
It will take time for the pigmentation to clear, but if symptoms worsen you should see your veterinarian who will probably want to do some blood work and check thyroid function. Please feel free to contact us again if you have any other questions or to update us on your progress.