Every dog will suffer with an upset stomach from time to time. One of the quickest and easiest ways to help a dog in this situation is by changing his diet. A chicken and rice recipe for dogs is one of the most commonly recommended remedy for dogs with an upset stomach. Read the full recipe here: https://topdogtips.com/chicken-and-rice-recipe-for-dogs/
You need to begin with small servings and gradually work your pet up to eating his regular meals again. It's best to start with 4-5 small portions of this food (or a similar recipe) for the first day. If your dog seems to keep the portions down, you can increase the serving size and feed 3-4 portions on the second day.
"The nutritional information below is based on a 1/2 cup serving size, the use of brown rice and the vegetable blend that I used. It may be different if you use white rice or a different combination of veggies."