What is vomiting?
Vomiting is defined as the forceful emptying of the contents of the stomach. It is caused by a signal from the brain to the stomach, which originates from a part of the brain called the vomiting center.
Vomiting initially developed because it helped animals survive poisoning. Nerves in the abdomen or certain substances in the blood signal to the brain that an animal may have ingested something toxic, and vomiting can help the body rid itself of the harmful substances. Although the actual threat of toxin ingestion is now less for pets than for their wild ancestors, more triggers have begun to induce the brain to send vomiting signals over time. However, prolonged vomiting can be dangerous because it can lead to life-threatening dehydration.
What are the causes of vomiting?
Primary gastric or intestinal conditions that can cause vomiting include: parasites, toxins, foreign objects, spoiled food, food allergies, gastric ulcers, inflammatory bowel disease, and cancer.
Secondary or non-gastric conditions that may cause vomiting include: motion sickness, thyroid disease (in cats), pancreatitis (inflammation of the pancreas), pyometra (uterine infection), kidney or liver disease, parvovirus or distemper in dogs, and feline panleukopenia virus.
How is the cause of vomiting diagnosed?
It is very important to distinguish between vomiting and regurgitation before attempting to diagnose the cause of your pet’s vomiting. Vomiting requires abdominal effort (contraction of abdominal muscles) and is the active expulsion of stomach contents. In contrast, regurgitation is the passive expulsion of contents from the esophagus without feeling nauseated or gagging. This distinction is important because the medical conditions that cause regurgitation are different from those associated with vomiting.
Once your pet’s vomiting has been confirmed, the veterinarian will begin the diagnosis and treatment process. To narrow down the possible causes, the veterinarian will consider your pet’s age and species. For example, a young and energetic dog vomiting is more likely to have eaten something they shouldn’t have, while an older cat with weight loss, increased drinking, and vomiting is more likely to have medical issues such as kidney disease or thyroid disease. Your veterinarian may ask detailed questions about the duration of the illness, weight loss, medications, changes in appetite, and the timing of the vomiting. A thorough physical examination will be performed to determine if there is abdominal pain, dehydration, or other abnormalities that could be causing the vomiting. You may be asked to bring some vomit to the hospital, as the appearance of the vomit can be helpful in diagnosis. For example, the presence of black coffee-ground-like material in the vomit suggests that there may be bleeding in the stomach.
The veterinarian may also recommend laboratory tests on blood, stool, and urine. X-rays and abdominal ultrasound may also be needed for evaluation. If the veterinarian suspects that the problem may be limited to the stomach and intestines near the stomach, an endoscopy may be recommended. This procedure requires anesthesia and involves looking down the esophagus and into the stomach and intestines of your pet using an endoscope, a long tube that contains a miniature camera.
How is vomiting treated?
Dehydration caused by prolonged or severe vomiting is an emergency issue, and your pet may need to be hospitalized for fluid replacement during the diagnostic process. The goal of treatment is to control the vomiting itself (to prevent further dehydration) and to control or eliminate the underlying cause of the vomiting. Some causes of vomiting are easy to treat, such as when a pet has an allergy to a certain food, and the vomiting stops when the diet is changed. On the other hand, pets with gastric cancer may require surgery, chemotherapy, or more long-term and aggressive treatment.
How can vomiting be prevented?
Vomiting is a signal to owners and veterinary teams that something is not right. If your pet vomits once, remove food and water for a few hours. Continuing to eat and drink may cause the vomiting to persist instead of stopping after a single episode. If your pet continues to vomit without anything to eat or drink, call your veterinarian and seek prompt medical attention.
