my pet has tummy issues. Now what?

In our latest episode of Not Just Fluff, host Hannah Shaw interviews two distinguished guests — Dr. Carl Winch, Senior Manager of Veterinary Relations at Banfield Pet Hospital, and Kayla Peters, a credentialed veterinary technician and community programs coordinator at Banfield Foundation — about gastrointestinal (GI) health in dogs and cats.

They dig into why digestive issues are more serious than many people realize, what causes them, and how veterinary teams work with caregivers to get to the root of the problem. 

GI upset: Why “common” doesn’t mean normal 

One of the biggest misconceptions in pet care is the belief that vomiting, diarrhea, or frequent belly discomfort is “just normal” — especially in cats. “People are prone to thinking that vomiting once or twice a week is normal, but that could be a sign of something a little bit deeper,” says Kayla.

“Any type of GI upset — whether it’s lip licking, seeming nauseous, or consistent vomiting or diarrhea — should always be monitored and looked into.” Nausea is never a routine state for health animals, so consider taking notes of even subtle changes.  

How age influences digestive health 

Age plays a significant role in how — and why — pets experience GI distress. 

Young pets 
Puppies and kittens are still developing their immune systems, making them more vulnerable to parasites and viruses. Stress from new environments, abrupt food changes, and exposure to unfamiliar pathogens are all common triggers. In many cases, GI upset in young pets points to parasites, dietary inconsistency, or infections like parvovirus, which can quickly become life-threatening. 

Older pets 
Senior dogs and cats may develop GI issues due to age-related changes, reduced tolerance to certain ingredients, or underlying illnesses affecting other organs. Food sensitivities also become more common with age. 

Regardless of life stage, digestive symptoms are signals that deserve careful evaluation. 

Why diarrhea in puppies and kittens is a big deal 

Diarrhea may seem minor, but for young animals it can be dangerous. They dehydrate quickly, and early GI signs can mask conditions like parvo. Kayla says, “Parvo starts with GI upset, lethargy, vomiting, diarrhea, and can turn very emergent very, very quickly.” Stress, rapid diet changes, vaccinations (or lack thereof), and environmental changes all contribute to digestive upset. 

Kayla explains that many new puppies experience diarrhea simply because they’re overwhelmed, or because their diets were switched abruptly without proper guidance. Diets should be changed over several days, gradually mixing the old and new food together. When diarrhea appears in a young pet, it’s important to treat it as a health priority. 

Parasites: The hidden culprits 

Parasites are among the most common causes of GI distress, but they’re often invisible to the naked eye. Dr. Winch explains, “Generally, we’re not going to see worms in their stools, because the worms are living in the intestines. It’s the microscopic eggs we’re looking for.” 

Tapeworms are an exception, often seen as rice-like segments on stool or fur. But many other parasites, like roundworms, hookworms, Giardia, and coccidia, require testing to identify.

Kayla stresses the importance of environmental cleaning after a parasite diagnosis. Even if the animal is treated, eggs and cysts can persist in grass, bedding, or carpet. Successful treatment means addressing both the pet and their surroundings.

Some parasites can also pose risks to humans — especially children — which makes testing and prevention even more essential. “There are some parasites puppies and kittens can get that can also be transmitted to humans… Roundworms are a good example,” says Dr. Winch. Make sure anyone cleaning up after pets thoroughly washes their hands afterward, especially before eating or drinking.

Understanding the gut microbiome 

The GI tract is home to a complex bacterial community known as the microbiome, which plays a significant role in digestion and immune function. When this ecosystem becomes unbalanced due to illness, stress, diet changes, or overgrowth of harmful bacteria, pets can develop diarrhea, vomiting, or chronic discomfort. 

Dr. Winch explains that antibiotics can disrupt this delicate balance. While antibiotics once were prescribed frequently for GI signs, veterinarians now take a more cautious approach, reserving them for cases where they are truly necessary. “Even after single courses of antibiotics, we see changes in the gut environment.

The secondary effects could be worse than what we’re trying to treat,” says Dr. Winch. Supporting the microbiome through proper nutrition and targeted supplements often plays a big role in recovery. 

Diet: A major factor in GI health 

Diet changes are one of the leading causes of GI upset. Even when caregivers say they’re only feeding “chicken,” how that chicken is prepared matters. “People say, ‘I just gave him chicken,’ but it’s chicken roasted with onions or a greasy rotisserie chicken. Dogs can’t digest the way we can,” says Kayla. 

Animals can develop pancreatitis and food sensitivities, especially with common proteins like chicken. Not every diet works for every pet, so paying close attention to stool quality, comfort, and reaction to new foods is essential.

Dr. Winch shares a memorable story of a longtime client whose dog developed persistent diarrhea: “She told me she’d been buying the same food. But one night she came in holding the bag saying, ‘I know what it is — you were right.’ The label had changed from ‘with soy’ to ‘with corn.’ One ingredient was enough to cause all that trouble.”

He adds, “Don’t underestimate subtle changes to the diet. They can have a big impact.” 

Viruses and preventive care 

Vaccines play a critical role in protecting young pets from devastating GI viruses. Parvovirus, one of the most feared diseases in dogs, spreads easily and progresses rapidly. Kayla stresses that staying up to date on vaccines — and avoiding high-risk areas like dog parks until puppies are fully vaccinated — is key to prevention. 

Chronic GI disease: There’s hope 

Chronic conditions like inflammatory bowel disease (IBD) can feel overwhelming at first, but many pets live full lives with the right management plan. From diet adjustments to supplements and medication, chronic GI disease often becomes a long-term collaboration between caregivers and veterinary teams. 

What to expect at a vet visit for GI issues 

When caregivers bring their pets in for GI concerns, the veterinary team moves into investigative mode. Kayla notes, “History is huge. Did they eat anything? Did the diet change? Any new pets or environments?” 

Dr. Winch adds: “If we’re showing any GI sign, I bring in a diet from the very beginning because you want to start that support.” 

Diagnostics often involve fecal testing, Giardia SNAP tests, X-rays, and possibly blood work.

Dr. Winch also explains how history shapes diagnostics: “If it’s a Labrador who’s off their food, I’m more concerned. Labs are never off their food.”  

Each clue helps determine the next step. 

In a nutshell 

GI health in dogs and cats is complex, but caregivers don’t have to navigate it alone. Whether facing parasites, diet challenges, stress-related GI signs, or chronic conditions, partnering with a veterinary team provides clarity, support, and effective solutions. Noticing symptoms early and seeking veterinary guidance can help make a difference. 

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Important Notice: The information provided on this page is for informational purposes only and is not a substitute for professional veterinary advice. Always consult a veterinarian with any questions regarding your pet's health or medical condition. Never disregard or delay seeking professional veterinary advice based on information from this page.