I purchased this shampoo to use on our Dogue de Bordeaux (French Mastiff) who has had skin issues from a young age. Someone from the Dogue de Bordeaux Rescue had recommended I try it. I was previously using a shampoo that only had 2%Benzoyl Peroxide in it and that just wasn't clearing his skin up. After using this product w/the combination of the 2% Benzoyl Peroxide AND sulfur, my dog's skin has dramatically improved. I use it every other week to shampoo him and am very pleased with the results. His skin is completely under control now and almost completely cleared up. Great product that I will continue to use.