Dog skin is closer to neutral pH than ours; human shampoo is built for more acidic skin. Dog skin is closer to neutral pH than ours; human shampoo is built for more acidic skin. If it’s fourteenth, behind three preservatives and the fragrance, “Oatmeal Formula” on the front is doing a lot of heavy lifting. Ingredients Worth Reaching ForA good everyday dog shampoo does its job with a short, recognizable list. Human shampoo is balanced for more acidic human skin, and repeated use dries a dog out and invites itching.