In terms of horse shampoos, your choices may seem endless, but there are a few issues to keep in mind when searching for one. The first is, what are you searching for in a shampoo? A shiny coat, help with dry or irritated skin, to remove stains? Different shampoos target different problems, so shop carefully. Concentrate on ingredients like tea tree oil or aloe for irritated skin. Oatmeal is effective for dry skin. Stain removers are effective, but can irritate skin. Be sure that with any new shampoo you try it out on a small area of your horse first in case there is any allergic reaction. And no people shampoo. Horses have a different pH – and different needs – than we do.