Gastritis in Dogs & Cats

Gastritis is a condition that describes inflammation, irritation or damage of the stomach lining and is one of the most common digestive disorders in dogs and cats. The stomach secretes gastric juice which is rich in hydrochloric acid and it needed for digestion. Gastric acid is produced by cells lining the stomach. When the stomach lining is irritated due to secretion of gastric acid, symptoms arise that may bring about pain and discomfort. Gastritis is always uncomfortable for affected animals, but fortunately it usually is not life-threatening.

Gastritis can be either sudden or slow in onset.  Sudden onset of gastritis is known as acute gastritis which always involves severe abdominal pain and persistent vomiting, whereas the slow onset refers to as chronic gastritis. Unfortunately, in many cases, the cause of the dog’s gastrointestinal discomfort will never be determined.

Acute gastritis

It occurs when dogs eat garbage, rotting or spoiled substances, toxic plants, caustic household chemicals, antifreeze, fertilizers, rodenticides or inanimate objects such as plastic wrap, bones, toys or needles. Some dogs develop sudden stomach inflammation from eating the feces of other animals or other unnatural articles of food; this unpleasant habit is called “pica.” Irritating medications, such as non-steroidal anti-inflammatory drugs, aspirin, corticosteroids and some antibiotics can also cause acute gastric inflammation.

Chronic gastritis

It is caused by long-term disruption of the mucosal lining and normal bacterial flora of the digestive tract. Prolonged gastrointestinal inflammation can be caused by ingestion of indigestible materials, such as plastic, rubber, paper, carpet remnants, hairballs or string. These items can remain in the stomach without being passed with the stools.

Bacterial and viral infections can also cause chronic gastritis. Parvovirus is a fairly common cause of severe gastritis, particularly in puppies that are not properly vaccinated. Distemper is another viral disease associated with chronic gastritis. Dogs that frequently eat grass or other plant material are prone to developing chronic gastrointestinal discomfort, as well.

Symptoms

• Loss of appetite
• Abdominal pain
• Weakness
• Lethargy
• Bad breath
• Weight loss
• Vomiting
• Regurgitation
• Flatulence
• Dehydration
• Diarrhea/Constipation
• Blood in the stool
• Dull hair coat
• Pale or yellow mucous membranes
• Excessive salivation

Diagnosis

Diagnosis of gastritis is based on the symptoms presented as well as a physical examination. Certain tests such as blood tests, urine samples, feces analysis, and x-rays may be taken to determine the cause of gastritis. Sometimes additional testing which includes an abdominal ultrasound, radiograph or endoscopy may also be performed.

Treatments

• Restrict food intake, avoiding further contact with whatever caused the condition for 12 to 48 hours.
• Ice (crushed or cubes) can be provided as the only source of water initially
• Administration of subcutaneous or intravenous fluids to rehydrate the dog and restore the proper balance of sodium, potassium and other electrolytes
• The initial diet should be soft, low-fat and bland, ideally from only one easily-digestible carbohydrate and one low-protein source. Cooked rice and potatoes are common starch sources for this diet
• Sources of protein include non-fat cottage cheese, skinless boiled white-meat chicken and boiled ground beef
• Meals should be given in small amounts and frequently, for at least 2 to 3 weeks, to assess whether the dog’s gastritis has fully resolved
• Antiemetics will help to stop vomiting, and antacids will help to coat the stomach lining. Metoclopramide (0.3 mg/kg, PO or SC, tid or 1–2 mg/kg/day 
• H2 receptor antagonists - used when stomach ulcers are suspected – ex; Cimetidine, Ranitidine, Nizatidine or Famotidine
• Proton pump inhibitor - such as Omeprazole - used in severe cases with stomach ulceration
• Antibiotics and medication that kills parasites are indicated in cases of bacterial or parasite related gastritis.
• Treatment of Helicobacter spp. in dogs usually entails a 2- to 3-week course of triple therapy:

1. Amoxicillin(20 mg / kg PO BID 14d), Metronidazole (20 mg / kg PO BID 14d) and Famotidine (0.5 mg / kg PO BID 14d)
2. Amoxicillin (20 mg / kg PO TID 2Id), Metronidazole (20 mg / kg PO TID 21d), and Omeprazole (0.7 mg PO SID 2Id)
3. Amoxicillin (20 mg / kg PO BID), Clarithromycin (7.5 mg / kg PO BID) and Metronidazole (10 mg / kg PO BID) for 14 days
4. Clarithromycin (30 mg PO BID 4d), Metronidazole (30 mg PO BID 4d), Ranitidine (10 mg PO BID 4d), and Bismuth (20 mg PO BID 4d)