If your dog gets a stomach ache or gastritis (inflammation of the stomach lining) then you can let the problem pass on its own or try to shorten the duration of the sickness. Puppies experiencing stomach problems should be seen by your local vet.
If your dog only has limited vomiting or diarrhea, can keep water down, and generally appears to be healthy you could stop food for a 24 hour period which can help calm the digestive tract but do not limit a dog’s water supply. Your dog needs to be closely monitored during this period for any serious signs of illness.
When a dog has repeated bouts of vomiting and/or diarrhea, the owner should try to find the culprit and remove it from the dog’s environment. Common causes can include dog foods made from cheap ingredients, eating certain plants, and human foods. Dogs may sneak into the rubbish when their owner isn’t watching and unfortunately, dogs are notorious for consuming things that aren’t good for them (ie: Chocolate).
It is important that you contact your local vet if your dog appears to be lethargic, continues vomiting, or has diarrhea for longer than a 24 hour period. Dogs can become dehydrated very quickly if they are unable to keep water in their system. Your Vet will be able to single out the source of the stomach ache and rule out any serious complications.
If your dog is experiencing severe vomiting and diarrhea, seek care immediately as this is a sign of parvovirus (parvo) which generally requires immediate care by your Vet. There are many serious disorders that can cause upset stomachs in dogs, if in doubt, always contact your local Vet.