Vomiting and diarrhea are clinical signs that may be seen together or separately in your pet. There are numerous causes of vomiting and diarrhea that range from a simple dietary indiscretion (“garbage gut”) to more complicated medical and surgical diseases such as a gastrointestinal foreign body obstruction, disease of the liver, pancreas, or kidneys, gastrointestinal infections, inflammatory diseases, endocrine diseases, and cancer.
Your pet’s medical history, age, and the onset and duration of signs can often differentiate between these types of gastrointestinal diseases. If your pet is experiencing a sudden onset of diarrhea and/or vomiting, many times a simple 24 hour fast can resolve any inflammation in the gastrointestinal tract. A fast with or without medications may be prescribed initially, since a high percentage of the cases presented respond with no other course of action necessary. Conditions such as gastrointestinal obstruction often require some time to diagnose because the GI tract is a dynamic organ system (i.e. it changes over time). Even if the pet has ingested a foreign object, it may not require surgery if the object can pass without causing a blockage. Often foreign objects do not show up on radiographs (x-rays) and some time must pass before an obstructive pattern is revealed. A fasting period allows for a time period that is important in deciding if the patient has a surgical problem or may be managed medically. Certainly, it the patient has been showing signs for days and is severely ill, a simple fast is not usually recommended.
A 24-hour fast is performed by completely restricting all food and water. At the end of the fast, a water trial is first performed. Give a small amount of water (1/4-1/2 cup, depending on the size of the patient) and then monitor the patient for nausea or vomiting. In one half-hour, repeat with another water trial. If there is no vomiting, a food trial is then performed. Give ¼ – ½ of the normally fed meal portion. We may recommend a bland diet of boiled white meat chicken and rice or provide you with a prescription bland diet). Give two to three small portions of food, and continue to closely monitor for vomiting, lack of appetite, nausea, drooling and lethargy. The goal is to allow the GI tract to rest initially, and then to prevent the pet from gorging on food and water when it is offered after the fast.
If your pet is still vomiting, it is then necessary to follow up with a repeat visit to us for a second physical examination. Radiographs or other blood tests may be necessary at this time.
If at any time your pet becomes weaker, more lethargic, is vomiting profusely, or if blood is seen in the vomit or in the diarrhea, please call us for advice immediately. If any diarrhea problem changes so that the diarrhea looks like pure water or like raspberry jam, this is an emergency and you should check with us immediately so that we can reexamine your pet.