Diy Dog Skin Allergy Treatment . 9 ways to improve your dog's skin and coat health. Blend a cup of oatmeal (or more, depending on the size of your pooch) until it’s a smooth powder. Pin on pets treatsfoods from www.pinterest.com Allow the paste to remain on your dog’s skin for 20 minutes before rinsing. Oatmeal is a natural moisturizer that is gentle and safe on your dog’s skin. Bathe your dog with a shampoo that contains oatmeal, aloe vera, or chamomile.