Vomiting occurs when the stomach is forcefully emptied, an occurrence that's typically considered a symptom of an underlying medical condition. The mechanics of vomiting are triggered by nerves in the GI tract or the presence of certain chemicals in the bloodstream. Before vomiting, either or both (nerves and/or chemicals) will signal the brain that it's time to empty the stomach of its contents.
A wide variety of medical conditions can lead to vomiting. Anything from simple motion sickness and dietary indiscretion (like garbage-eating, ingestion of foreign material, and a too-sudden change in diet) to poisoning and specific gastrointestinal ailments (including parasites, gastrointestinal viruses, dietary intolerances, cancers, and congenital abnormalities affecting the GI tract) can occasion vomiting.
These diseases can be categorized as either primary (gastrointestinal) diseases or secondary (non-gastrointestinal) diseases: Primary diseases that can cause vomiting include GI parasites, GI viruses, toxins, foreign bodies, food allergies or intolerances, inflammatory bowel disease, and primary gastrointestinal cancers.
Secondary diseases that can cause vomiting include motion sickness, hyperthyroidism in cats, Addison's disease in dogs, pancreatitis, pyometra, kidney disease, and liver disease.
Symptoms and Identification
Dogs and cats who vomit will exert abdominal effort in so doing. This is an important factor to observe, as pets who retch and pass ingested content without abdominal effort or nausea are typically regurgitating -- not vomiting. Regurgitation is a completely distinct symptom that must always be differentiated from vomiting as it's the result of a completely different set of conditions. Determining the underlying cause is typically the focus of diagnostic testing in the case of vomiting. This may include...
Fecal examination via microscopy
Complete blood count
Serum biochemistry analysis
Thyroid testing (in cats)
Abdominal X-rays (with or without contrast)
Specific testing for viruses, bacteria, and other pathogens
Specific testing for vomiting-inciting diseases (Addison's disease, etc.)
Endoscopy and/or colonoscopy
CT scans (especially if certain cancers are suspected)
No breed predisposition has been noted for vomiting in either dogs or cats. However, some of the underlying causes of vomiting are influenced by genetic factors predisposing pets to these diseases. Therefore, breeds of dogs and cats genetically predisposed to any of vomiting's underlying conditions will naturally be overrepresented.
Treatment varies but usually includes special medications and/or diets to relieve the vomiting itself and treatment to correct any fluid and electrolyte imbalances that occur as a result of vomiting. This, along with whatever treatment is required to address the vomiting's underlying cause are the typical therapeutic approaches to vomiting. This may include:
Dewormers and other parasiticides
Corticosteroids and/or other drugs
Fluid therapy to rehydrate and reestablish normal electrolyte balance
Puppies and kittens, along with small dogs and cats, merit immediately veterinary attention, as they can become dehydrated very quickly after the onset of vomiting. So, too, should pets showing any signs of diarrhea or lethargy see a veterinarian -- immediately.
The cost of diagnosis and treatment of vomiting depends greatly on its underlying cause. Owners of pets with conditions that require expensive hospitalization, elude easy diagnosis, and/or demand a lifetime of management via medication and or diet (often a very expensive proposition) may face extreme expenses in both the long and short term.
Prevention of vomiting is typically undertaken by refraining to offer pets foodstuffs and/or foreign material that do not correspond to their normal dietary repertoire.
Vaccination against specific diseases that lead to vomiting is also strongly recommended by way of effective prevention.
Pets suffering a host of disease states that predispose them to vomiting, however, will typically be unmanageable via these particular methods. In these cases, preventing the underlying cause -- if possible -- is the only rational approach.
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