Chihuahuas are small dogs with large personalities. When they don't feel well, they will let you know. If yours is suffering from an upset stomach and is vomiting or has diarrhea, this problem can become serious very quickly. Chihuahuas are often very small, and because of this, they can become dehydrated in a short period of time. Therefore, as soon as your chihuahua starts displaying signs of an upset stomach, begin caring for it immediately.
Withhold any food or water. When an animal has an upset stomach, it is often helpful to give the tummy a break. This will not only help the stomach feel better, but it will prevent even more vomiting or diarrhea from occurring.
Call your veterinarian. Vomiting and diarrhea can cause dehydration. Because of a chihuahua's small size, it only takes a small amount of fluid loss to cause a problem. A veterinarian can determine whether or not the chihuahua is dehydrated upon examination. If he believes your pooch is dehydrated, he will likely administer fluid therapy, either intravenously or subcutaneously.
Collect a sample of your chihuahua's stool, if possible. The veterinarian will likely run tests on the sample to look for parasites and bacteria. Parasites are often a common culprit of diarrhea.
Relay any information regarding your chihuahua's behavior to the doctor. Chihuahua's aren't notorious garbage eaters as are some dogs—such as labrador retrievers—so the veterinarian may not consider this to be a contributing factor. If yours is, it is important to tell your doctor of anything your chihuahua may have gotten into. In addition, tell the veterinarian about any interaction your chihuahua has had with other animals, as vomiting and diarrhea are often caused by viruses or parasites contracted from other animals. Fortunately, as a breed, chihuahuas aren't typically prone to gastrointestinal health issues, such as pancreatitis. Therefore, the upset stomach is probably an acute issue that will go away.
Feed your chihuahua a bland diet once the veterinarian has given you permission to provide food. The doctor may want food withheld for 24 hours. After that, feeding rice with boiled chicken or ground beef is typically advisable. Only feed small amounts at a time, and offer small amounts of water as well. The doctor may prescribe a premade bland diet, such as Hill's I/D or Purina E/N. These diets are designed to be easy on the stomach but provide the nutritional requirements needed.