How to settle a dog's upset stomach
This is probably a lot simpler than what you are thinking.
Having been brought up around dogs and my mum being a kennel club breeder I have kind of learnt a few things. We have had chihuahuas, poodles, whippets, pugs, Chinese cresteds, Yorkshire terrier, English bulldog and a Papillion. Maybe a few more but I can't remember.
All dogs are known to be prone to different diseases and problems due to the breed of dog and sizes etc as are humans. So you will sometimes need to check that how you treat them for one problem will not irritate another or bring another to the surface. Again that is very much the same with us humans.
In some cases owners do not know what they are doing with a dog they allow it to eat bits that it should not and that can lead to a lot of problems including upset stomachaches. If you are one of these owners and your dog is eating a lot of meat and chocolate which is very bad for them then just issue them dry biscuit and refrain any meat from the diet for a few days and no more chocolate.
However dogs can have off days like us and can become irritated and an upset stomachache just seems to flush things out of the system. We found and were told by our vets to do as you would with a human.
You should buy some rice and boil it. Depending on size of dog will depend on how much you should give it and then boil some chicken though not too much as it is meat. On the day you notice the bad belly give them the chicken and rice that night and try not to allow them anything before hand though a biscuit would be ok if they are not too ill. Then the next day feed them the chicken and rice morning and night and do the same for a third day just to make sure you don't irritate the stomach again. Day four give them the usual dog food though try to limit the meat a little.
So as you can see it is very simple and just as you would do with your child. I remember when I was little I would only be allowed dry food such as dry bread or crackers and then chicken and rice when my belly was better. I would spend a whole week being limited on dairy produce and known irritants.
If the dog continues to feel bad take it to the vets as they may need a specially designed diet. One of my mums dogs is currently on one and the other cant have meat but that is more due to his age.