Gastroenteritis in Dogs: Causes, Symptoms and Treatment

Gastroenteritis in dogs is inflammation of the stomach and intestines. Gastroenteritis, or stomach upset, is prevalent in dogs.

The causes of gastroenteritis in dogs include dietary indiscretions, sudden food switches, bacteria, viruses, parasites, food allergies, gastric ulcers, toxins, foreign bodies, GIT obstructions, cancers, endocrine conditions, and problems with the pancreas, liver, or kidneys. Stomach bugs in dogs are not caused by gastrointestinal parasites. Gastroenteritis is not an allergy, but specific allergies in dogs trigger gastroenteritis.

Dog vomiting and diarrhea are telltale symptoms of stomach upset. Gastroenteritis symptoms include nausea, abdominal pain, reduced or absent appetite, weight loss, dehydration, lethargy, and fever. 

Gastroenteritis in dogs is treated medically or surgically, depending on the underlying cause. Dietary modification and probiotics for dogs aid recovery from stomach upset.

The answer is yes, for pet owners asking, “Can dogs get stomach bugs?” Stomach bugs or stomach flu are viral gastroenteritis and require veterinary treatment. 

What is Canine Gastroenteritis?

Canine gastroenteritis is inflammation of the stomach and intestines. The medical terms are gastritis and enteritis. Gastroenteritis is referred to as an upset stomach. 

Gastroenteritis in dogs is a “common cause for acute-onset vomiting, anorexia, and diarrhea in dogs,” says a study, “Gastroenteritis,” published in Small Animal Critical Care Medicine in 2014. 

The stomach and intestines are sensitive and exposed to irritants, allergens, infectious agents, and parasites, predisposing them to dog digestive problems. 

Dog gastroenteritis is widespread and affects up to 50% of the canine population, according to a study, “Prevalence of Gastroenteritis in Dogs,” published in InterConf in 2023. 

Dog vomiting and diarrhea caused by gastroenteritis worsen and culminate in life-threatening dehydration when untreated. Prompt and adequate treatment is necessary to manage gastroenteritis dog poop and vomiting. 

What Causes Gastroenteritis in Dogs?

The causes of gastroenteritis in dogs are listed below. 

• Dietary Indiscretions: Dietary indiscretions mean a dog eats something harmful and are a leading cause of gastroenteritis in dogs. Indiscretions include eating garbage, human table scraps, cat poop, or non-edible items. 
• Sudden Food Changes: Switching from one dog food formula to another suddenly triggers stomach upset. Puppies are susceptible to sudden food changes. 
• Bacterial Infections: Bacteria such as E. coli, Salmonella, Clostridium, and Campylobacter cause gastroenteritis in dogs.  
• Viral Infections: Parvovirus, coronavirus, and distemper trigger gastroenteritis in dogs. Viral gastroenteritis in dogs is potentially life-threatening. 
• Parasites: Two types of parasites, worms (roundworms, tapeworms, hookworms, and whipworms) and protozoa (Giardia and Coccidia), cause gastroenteritis in dogs.  
• Food Allergies: Stomach upset in dogs is caused by allergens found in food, such as the proteins in beef, chicken, eggs, dairy products, and gluten. 
• Gastric Ulcers: Gastric ulcers are deep defects in the stomach lining caused by irresponsible use of non-steroid anti-inflammatory drugs and liver disease. They cause gastroenteritis in dogs.
• Toxins: Toxins cause gastroenteritis when a dog ingests them. Intoxications, such as antifreeze, pesticides, and insecticides, are emergencies requiring urgent vet care. 
• Foreign Body Ingestion: Foreign objects cause gastroenteritis in dogs. Dogs are naturally curious and explore objects through their mouths.
• Intestinal Obstruction: Intestinal obstruction in dogs due to foreign bodies, cancers, heavy parasitic infestation, or hernias results in acute gastroenteritis. 
• Gastrointestinal Cancer: Gastrointestinal cancer occurs in older dogs but is rare. The three types of gastrointestinal cancer are adenocarcinoma, lymphoma, and leiomyoma. 
• Endocrine Conditions: Stomach upset in some dogs is associated with hormonal diseases, such as hyperadrenocorticism, hypothyroidism, and diabetes mellitus. 
• Pancreas, Kidney, or Liver Issues: Inflammation of the pancreas and kidney and liver failure sometimes manifest with dog gastroenteritis. 

What are the Symptoms of Gastroenteritis in Dogs?

The symptoms of gastroenteritis in dogs are listed below. 

• Vomiting: Sudden and intense vomiting is a gastroenteritis sign. The vomit contains blood (hematemesis), depending on the underlying condition.
• Nausea: Nausea is common in dogs with inflamed stomachs and intestines. Nausea manifests with drooling and frequent swallowing. 
• Diarrhea: Diarrhea is a telltale sign of gastroenteritis in dogs and contains dark blood (melena) or fresh, red blood (hematochezia), depending on the underlying condition. 
• Appetite Loss: Reduced or absent appetite (medically known as anorexia) is a frequent symptom of stomach and intestinal inflammation in dogs. 
• Abdominal Pain: Dogs with gastroenteritis develop abdominal pain. The intensity of the pain depends on the underlying cause and ranges from mild to moderate to severe.  
• Dehydration: Prolonged and intense vomiting and diarrhea cause dehydration and are symptoms of gastroenteritis. Signs of dehydration include loss of skin elasticity, sticky saliva, sunken eyes, and dry nose. 
• Weight Loss: Persistent vomiting, diarrhea, and reduced appetite lead to weight loss in dogs with chronic gastroenteritis. 
• Lethargy: Dehydration combined with low or absent food intake and abdominal pain cause lethargy. Lethargic dogs are disinterested in daily activities and prefer to sleep. 
• Fever: A low-grade fever (slightly over 103°F) is one of the common symptoms of intestinal bacterial infection in dogs.

How Does Gastroenteritis Affect Dog Vomiting and Diarrhea?

Gastroenteritis affects dog vomiting and diarrhea by triggering episodes. Vomiting and diarrhea are the hallmark signs of stomach upset. 

Vomiting and diarrhea episodes are intermittent and debilitating. Intense vomiting produces foamy or yellowish bile once the stomach content is expelled. The diarrhea sometimes contains mucus or blood, which is considered an emergency.

 Dogs get dehydrated after long periods of vomiting and diarrhea. Signs of dehydration include sunken eyes, dry nose, loss of skin elasticity, sticky nose, and lethargy.

Can Dogs Get Stomach Bugs that Cause Gastroenteritis?

Yes, dogs can get stomach bugs that cause gastroenteritis. Stomach bugs or stomach flu describes gastroenteritis of viral origin and is borrowed from human medicine. 

Stomach bugs or flu are usually mild, and dogs recover quickly with hydration support and diet modifications. Viruses that cause stomach flu in humans, like rotavirus and norovirus, are transmissible to dogs. 

Stomach bugs in dogs are not related to or caused by gastrointestinal parasites. 

Is Gastroenteritis in Dogs Serious?

Yes, gastroenteritis in dogs is serious. The severity of gastroenteritis depends on the underlying cause. The most serious form is hemorrhagic gastroenteritis (HGE). 

“Hemorrhagic gastroenteritis, renamed acute hemorrhagic diarrhea syndrome (AHDS),” is “more prevalent in young, small breed dogs,” reports a study “Hemorrhagic Gastroenteritis,” published in the Textbook of Small Animal Emergency Medicine in 2018. 

Hemorrhagic gastroenteritis is a sudden and potentially life-threatening dog disorder that manifests with vomiting and bloody diarrhea.

The exact cause of HGE is unknown, but the bacteria Clostridium perfringens type A is believed to be involved in the pathogenesis. 

Dogs with hemorrhagic gastroenteritis are at risk of developing septic, and prompt and aggressive treatment is critical for dogs with HGE. 

How to Treat Gastroenteritis in Dogs?

Treat gastroenteritis in dogs by ensuring hydration, relieving the symptoms, and managing the underlying cause. 

Treatment for stomach upset includes intravenous fluids, antibiotics, antacids, antiemetics, antidiarrheal meds, appetite stimulants, bland diet, feeding tubes, dietary changes, surgery, probiotics, and prebiotics. 

Intravenous fluids are the cornerstone of gastroenteritis treatment. Fluid therapy restores the lost electrolytes, manages dehydration, and administers medication in vomiting dogs. 

Antibiotics are used in dogs with bacterial gastroenteritis and at high risk of secondary bacterial infections. Metronidazole and ampicilin are the preferred antibiotics for treating bacterial gastroenteritis. 

Antacids, such as famotidine (Pepcid) and ranitidine (Zantac), treat gastroenteritis by reducing stomach acid and protecting against it. 

Antiemetics are medications that stop vomiting. Veterinarians use metoclopramide (Reglan) and maropitant (Cerenia) as antiemetics. 

Antidiarrheal medications reduce the severity and intensity of diarrhea episodes by reducing intestinal motility. Antidiarrheal medications include kaolin-pectin, activated charcoal, and bismuth subsalicylate. 

Appetite stimulants, such as mirtazapine (Mitraz) and Capromorelin (Entyce), promote food intake. 

A bland diet is recommended in the first few days of treatment and recovery because it gives the dog essential nutrients without exerting the stomach. The best bland diet recipe combines boiled white rice with chicken meat.  

Feeding tubes are reserved for severe cases of gastroenteritis and hospitalized dogs. The vet inserts a tube into the dog’s stomach and uses the tube to administer food. 

Gastroenteritis caused by food allergy or sensitivity is treated with dietary changes.

Surgery is the treatment for dogs with foreign objects, gastrointestinal obstructions, and certain types of gastrointestinal cancers. 

Probiotics and prebiotics are dietary supplements that promote gut health and treat gastroenteritis. Probiotics are live beneficial bacteria and yeasts, while prebiotics are fiber that are food for the probiotics. 

What are the Recovery Signs of Gastroenteritis in Dogs?

Recovery signs of gastroenteritis in dogs are improved vomiting and diarrhea. Improved vomiting and diarrhea are expected within one to two days of treatment. 

The vomiting or diarrhea episodes are less frequent and intense, and the dog shows interest in food. A bland diet is recommended when the dog shows signs of appetite. The bland diet of boiled white chicken meat and rice nourishes the dog without straining the stomach. 

The overall recovery time depends on the underlying cause, which ranges from several days to weeks. 

What Preventive Measures Can You Take Against Gastroenteritis in Dogs?

Preventative measures you can take against gastroenteritis in dogs include a high-quality diet, gradual food switches, digestive supplements, discouraging scavenging and trash raiding, and regular vaccination and deworming. 

Feed the dog an easily digestible diet suitable for its age, lifestyle, and needs. Do not make sudden formula changes, and use supplements such as probiotics and dietary fiber. 

Discourage unwanted behaviors like scavenging and trash raiding early to minimize the risk of dietary indiscretions. 

Ensure the dog is updated on vaccinations and deworming to prevent infectious gastroenteritis and intestinal worm infestations. 

Can Pancreatitis in Dogs Lead to Gastroenteritis?

Yes, pancreatitis in dogs can lead to gastroenteritis. Inflammation of the pancreas causes symptoms overlapping with stomach upset, including vomiting, diarrhea, and abdominal pain. 

An inflamed pancreas produces less trypsin, which alters the gut microbiota and triggers gastroenteritis, according to a study, “A Novel Pore-Forming Toxin in Type A Clostridium perfringens Is Associated with Both Fatal Canine Hemorrhagic Gastroenteritis and Fatal Foal Necrotizing Enterocolitis” published in PlosONE in 2015. 

The pancreas secretes antimicrobials like CRAMPs (cathelicidin-related antimicrobial peptides), which modulate the microbiome and cause inflammation and gut responses. Pancreatitis in dogs affects this function. 

A study, “Beyond Digestion: The Pancreas Shapes Intestinal Microbiota and Immunity,” published in Cell Metabolism in 2017, examines the pancreatic effect on gut bacteria. 

Can Probiotics Help Treat Gastroenteritis in Dogs?

Yes, probiotics can help treat gastroenteritis in dogs. Probiotics are important in gastroenteritis treatment. 

Probiotics accelerate the normalization of the dog’s intestinal microbiome, reports a study, “Effect of Probiotic Treatment on the Clinical Course, Intestinal Microbiome, and Toxigenic Clostridium perfringens in Dogs with Acute Hemorrhagic Diarrhea,” published in PlosONE in 2018. 

Probiotics in dogs support the growth of beneficial bacteria in the gut. Maintaining a healthy gut microbiome is critical for treating inflammatory conditions of the stomach and intestines. 

“Puppies with gastroenteritis symptoms receiving a multi-strain probiotic had rapid improvement, implying beneficial effects on the microbiota and its functionality,” says a study “A Multi-Strain Probiotic Promoted Recovery of Puppies from Gastroenteritis in a Randomized, Double-Blind, Placebo-Controlled Study,” published in the Canadian Veterinary Journal in 2023. 

What are the Best Probiotics for Gastroenteritis in Dogs?

The best probiotics for gastroenteritis in dogs are listed below. 

• Honest Paws Pre + Probiotics: Honest Paws Pre + Probiotics is a powdered, chicken-flavored product containing a potent formula of 5 billion Colony-Forming Units (CFUs) and premium prebiotics. The supplement is packed in single-dose sachets for practical dosing and treating gastroenteritis. 
• PetLab Co. Probiotics for Dogs: PetLab Co. soft chews feature eight strains of live, beneficial bacteria and gut-boosting ingredients like agave, honey, and salmon oil. The chews are pork-flavored and easy to use. 
• Purina FortiFlora Probiotics: The Purina single-strain supplement was voted the best vet-recommended probiotic in 2019. It contains E. faecium and beef-flavored powder that is packed in individual sachets.   
• Open Farm Probiotic Chews: The probiotic chew is formulated with 100% traceable ingredients, including seven strains of probiotics, pumpkin, and ginger. It is one of the best probiotics for dogs on the market. 

When Should You Seek Veterinary Help for A Dog Showing Symptoms of Gastroenteritis?

You should see veterinary help for a dog showing symptoms of gastroenteritis if the vomiting and diarrhea do not improve within 48 hours. 

Simple stomach upset is managed at home by withholding food and a bland diet. Contact a vet if the home treatment is not successful. 

Call the veterinarian immediately if the stomach upset signs are accompanied by worrisome symptoms like blood in the stool or vomit, fever, dehydration, and extreme lethargy. 

Can Dog's Diet Influence the Development of Gastroenteritis?

Yes, a dog’s diet can influence the development of gastroenteritis. Diet affects stomach and intestinal inflammation in terms of quality and quantity. 

Food-related problems cause stomach upset, and correct food choices are critical for successful gastroenteritis treatment. 

The ideal diet for dogs with digestive problems is low in fat and rich in easily digestible fiber. Dogs with food sensitivities require special diets made with hydrolyzed or novel proteins. 

Consult the veterinarian for a food recommendation that suits the dog’s needs, considering age, lifestyle, and health. 

Is Gastroenteritis a Kind of Allergy in Dogs?

No, gastroenteritis is not a kind of allergy in dogs. Gastroenteritis is inflammation of the dog's stomach and intestines. Certain allergies, however, trigger gastroenteritis. 

Food allergies manifest with stomach upsets, like vomiting and diarrhea, which are standard for gastroenteritis. Common causes of food allergies in dogs include chicken, beef, eggs, dairy, and gluten.