Every dog is different from another. Some dogs are like food machines that can break down anything edible while others have highly sensitive stomachs.
Generally, dogs with sensitive stomachs are characterized by having mild symptoms that range from occasional vomiting, stool problems (soft or too hard), and flatulence. A visit to a veterinarian is advisable when the symptoms become serious and unbearable.
Once possible serious conditions have been ruled out, you may now start examining the other possible causes of your dog's stomach sensitivity. Some canine--especially senior dogs--have stomachs that can be easily irritated by certain ingredients in their diet. For instance, some dogs cannot tolerate certain types of proteins. If this case is similar to your dog, overhauling your dog's diet is one way to solve this. You may try to find alternative sources of protein as a substitute for the protein you're currently feeding your pooch.
Figuring out the foods that are causing your dog's sensitive stomach is challenging. But it surely goes a long way. Not only it gives you a better understanding of your pet's sensitivities, but it also makes meal planning and food preparation a breeze.