Vomiting is defined as the forceful discharge of ingested material from the stomach and sometimes part of the small intestines (yellow bile), which is initiated by the central nervous system. It is a common clinical sign in small animals. It is a protective mechanism developed to remove potentially damaging ingested substances. Vomiting is associated with many pathologic conditions, gastrointestinal disease, bowel obstruction, systemic or metabolic disease, and toxicity (poisons, drugs). Severe vomiting can result in serious consequences, including volume depletion (dehydration), acid-base and electrolyte disturbance, esophagitis, aspiration pneumonia and malnutrition.

Vomiting is a protective reflex initiated by the central nervous system consisting of three stages: nausea, retching, and subsequently expulsion of the gastric content. Specific signs of animals with acute vomiting will depend on the underlying cause, however, most animals will present:

There are several possible etiologies for acute vomiting; some of the most common causes are:

Gathering a complete history of the patient is the first and most important step in the diagnosis of acute vomiting. It is crucial to provide the veterinarian with as much information as possible about the signs, history and a thorough description of the vomiting episodes.

The veterinarian needs to differentiate the owner's report of vomiting from gagging, coughing, dysphagia, or regurgitation. Vaccination status, travel history, previous medical problems, and current and previous medication should be provided. Many drugs, such as non-steroidal anti-inflammatory drugs (NSAIDs), can result in vomiting. The possibility of an intoxication, foreign body ingestion and metabolic disease should be considered. For example, frequent urination, increased water intake and weight loss are typical of vomiting associated with diabetes or chronic kidney failure.

A complete physical description of the vomited material and a dietary history are needed because vomiting may be associated with an adverse reaction to food. Vomiting of an undigested or a partly digested meal more than 6 to 8 hours after eating, a time at which the stomach should normally be empty, suggests a gastric problem. On the other hand, vomit-containing bile (yellow vomit) makes a gastric obstruction unlikely. Vomit having a fecal odor suggests problem in the small intestine. Presence of blood can indicate a gastric ulcer, which can be related to metabolic conditions, reaction to certain drugs, clotting abnormalities, gastritis, or neoplasia.

After a complete history and physical examination lab work including an intestinal parasite screen and radiographs will aid in the diagnosis.

The gastro intestinal tract is very resilient and there are many cases of pets with clinical signs of acute vomiting and/or diarrhea that resolve spontaneously. However, in some cases acute vomiting can be a sign of a life-threatening disorder, which if not identified and treated, could lead to death of the pet. Depending on the final diagnosis, your pet may need a special or prescription diet (bland easily digestable). Patients that present vomiting due to renal failure may need a prescription diet with specific amounts of calcium, phosphorus and high quality protein. In cases of vomiting due to food allergy or dietary sensitivity, it is important to identify which ingredient is causing the problem and eliminate it from the diet.