Vomiting and diarrhea are quite common in cats, largely due to their indiscriminate (not terribly selective) eating habits. It is important to realize that an occasional bout of vomiting and diarrhea can be normal in a healthy animal, and may occur as often as a couple of times in a month. The question that needs to be answered is when is the problem serious enough for you to seek veterinary care and potential hospitalization for your pet? Acute vomiting and diarrhea is addressed quite differently from chronic vomiting and diarrhea with regard to the diseases that cause each, diagnostic plans, and treatment regimes.
In patients that are otherwise feeling well without concurrent problems, symptomatic therapy is recommended, and usually curative. This involves removing all food and water for a period of several hours, and gradually reintroducing a bland diet for several days prior to reinstituting your pet's regular diet. If the problem recurs once your pet is fed, or the problem persists despite being held off food, your pet should be evaluated by a veterinarian in a timely fashion. In addition, if your pet seems painful, in distress, or you notice red or dark brown/black vomitus or diarrhea (suggestive of internal bleeding), one should seek veterinary attention at once. Cats and small dogs are particularly prone to dehydration and hypoglycemia in the face of prolonged vomiting and diarrhea, therefore should be watched very carefully. Prolonged, frequent vomiting and diarrhea can lead to severe dehydration, shock, and potentially death if not addressed in a timely fashion.
There are many causes of acute vomiting and diarrhea. Although many of these patients have self-limiting disease, and respond nicely to symptomatic therapy, some causes of acute vomiting and diarrhea can be life threatening, and initially, may be difficult to differentiate from more benign disorders. Dietary indiscretion includes eating spoiled food, over eating, ingesting foreign material and sudden dietary changes.
Dietary intolerance most often occurs because of a particular protein, but can be associated with lactose, diets high in fat and certain food additives.
There are many infectious agents that can cause acute vomiting and diarrhea:
Bacterial (Salmonella, Clostridium)
Fungal (Histoplasmosis, aspergillosis)
Parasitic (roundworm, hookworm, giardia)
Viral (Feline infectious peritonitis, feline leukemia and feline immunodeficiency related disease)
Drugs and toxins can cause vomiting and diarrhea by directly irritating the lining of the gastrointestinal tract. Examples include anti-inflammatory agents (aspirin, corticosteroids), antibiotics, anti-cancer drugs, insecticides, heavy metals, and pesticides.
Gastrointestinal obstruction/blockage often causes vomiting and diarrhea. Foreign bodies, tumors, intussusceptions (telescoping of the bowel into itself) and parasites are the most common causes of obstruction.
Metabolic disorders such as kidney and liver disease, hyperthyroidism and diabetes mellitus are often associated with vomiting and diarrhea.
Abdominal disorders such as pancreatitis (inflammation of the pancreas), peritonitis (inflammation of the abdominal cavity), pyometra (infected uterus), prostatitis (inflammation of the prostate) and sepsis (systemic infection) are often associated with an acute onset of vomiting and diarrhea.
Inflammatory bowel disease (IBD) is a microscopic accumulation of inflammatory cells of any/all parts of the gastrointestinal tract. IBD is most often associated with chronic vomiting and diarrhea, although there are cases that present rather acutely.
Gastroduodenal ulcers can be associated with liver, kidney, or pancreatic disease. Acute vomiting and diarrhea, with or without blood, are often the first signs exhibited by the pet.
Stress can cause a combination of acute vomiting and diarrhea.
Lymphosarcoma is most often a microscopic accumulation of cancerous cells within the gastrointestinal wall. Although signs are usually that of chronic vomiting and diarrhea, occasionally acute signs develop first.