If your dog is able to keep down some water, you can then try offering some clear liquids such as plain Pedialyte, Gatorade, apple juice diluted… The most common signs of upset stomach in dogs are diarrhea and vomiting. If your dog is nauseous, you may also see him eat grass to soothe his stomach… Pumpkin, sweet potatoes, bananas, and oatmeal are gentle foods that can be added to your dog’s meal to help settle the stomach…