Diarrhoea and vomiting in dogs and cats: what to do with an upset stomach

Vomiting and diarrhoea are among the most common issues faced by cats and dogs. It's a common thing to see at emergency veterinary practices.

Vomiting is consistently one of the most common pet insurance claims insurers see too. The good news is many cases of gastrointestinal (GI) upset can be resolved with supportive care and time. The less good news, however, is that GI upset can also be a serious problem.

But how can pet parents know when to be worried? Let’s take a deeper dive into GI upset and how you can look after your pets.

Causes of diarrhoea and vomiting in dogs and cats

Many pet parents wonder what causes diarrhoea and vomiting in dogs and cats. It’s important to note that these symptoms, like diarrhoea vomiting in dogs or cats, may not always originate in the gut.

Almost any of our pet diseases can present with vomiting as the primary concern owners bring up at the vet.

Here’s a list of causes of diarrhoea and vomiting in pets that come to mind.

Gastrointestinal causes of vomiting and diarrhoea in cats and dogs

• Parasites

• Dietary indiscretion (I ate something I shouldn't have)

• Allergies

• Infectious causes (bacteria/viruses)

• Foreign bodies/gut obstructions

• Toxins

• Primary GI disease (food allergy or inflammatory bowel disease)

• Pancreatitis

• Abrupt changes in diet

Non-gastrointestinal causes of vomiting and diarrhoea in cats and dogs

• Kidney disease

• Liver disease

• Diabetes

• Hyperthyroidism

• Cancer

• Addison’s disease (hypoadrenocorticism)

• Vestibular issue (like vertigo in people)

• Side effects of some medications

• Stress or anxiety

I could go on, but I think this list helps give people an idea of how non-specific vomiting and diarrhoea are as a clinical sign in our pets.

It’s important for pet owners to keep this in mind when seeking veterinary care for tummy upset because any hints from the pet's history leading up to the event can help find the cause and treat the problem.

What does your pet’s vomit or diarrhoea mean?

We know talking about what your pet’s vomit or diarrhoea looks like is not everyone’s favourite topic of conversation, but your vet is usually keen on a description or a picture.

It can really help us figure out what caused it, as well as how serious the scenario might be.

Some pet vomit colours to look out for are:

• Vomiting yellow fluid – Pet parents often get concerned when they see bright yellow in their pets' vomit. This is a compound called bile, which will often come from the early part of the small intestines. Typically you’ll see bile in your pet’s vomit if they are throwing up on an empty stomach. This yellow colour isn’t necessarily a source of panic, but we’ll touch more on when to seek vet care later!

• Vomiting blood – This definitely warrants a trip to your friendly neighbourhood vet. Blood in your pet’s vomit may indicate ulcers, toxins, perforations in the gut, or bleeding problems.

• Diarrhoea with blood – Dark black/tarry stools are a concern when it comes to diarrhoea as this usually means there is blood being digested/bleeding happening higher up in the gut. Poo with bright red blood is usually coming from the colon (lower gut) and has a long list of causes, including stress!

• Eating grass and vomiting – Some pets eat grass when they feel nauseous, but honestly, most of them do it because they’re bored or they like it. My dog loves to eat grass and sometimes I wonder if he was a cow in another life.

Should you starve a dog with diarrhoea?

No, you shouldn’t starve a dog with diarrhoea unless your vet advises otherwise.

In most cases, allow a short fasting period (a few hours) and then offer bland food such as boiled chicken with plain white rice.

Puppies and small dogs should never be starved as they lack energy reserves. Always ensure your pet has access to water.

For most healthy adults, giving them a few hours post-vomiting to let them settle and then offering a small amount of their food or something bland is typically safe.

For example, if your dog vomits one time and is otherwise happy and still interested in food, I would tell a client to give them a break for the afternoon and then offer a third to half of their normal food amount for dinner.

If they keep this down you can slowly work back to full amounts over the next few days. I never recommend withholding water.

Repeated episodes of GI upset or your pet showing other clinical signs should warrant a trip to your vet for further investigation. Concerning changes at home would include them being lethargic, weak, not interested in food, disoriented, or even restless and agitated.

What should I give to my cat or dog experiencing stomach upset?

What to give a dog vomiting and diarrhoea? Bland and easily digestible foods like boiled chicken breast or turkey with white rice or boiled sweet potato are great options. Avoid fibre-heavy foods like pumpkin as they aren’t practical for pets.

I don’t often recommend people use things like sweet potato, pumpkin or squash for fibre supplementation because the amount you need to give to make an impact is fairly large – it's just not practical.

Similarly, I don’t often recommend chicken and rice for diarrhoea cases because that’s just protein and starch with little fibre, so it usually goes in one end and out the other.

Feeding a combination of things like this is ok for short-term use only, as it’s more of a supportive measure and not a long-term balanced diet.

Using a veterinary gut support diet like Royal Canin Gastrointestinal is a safe bet if people want something easy and balanced. It comes in wet and dry for both dogs and cats. Veterinary diets like this one are balanced maintenance diets for pets and potentially can be fed long-term for those with a sensitive gut.

When should I see a vet about vomiting and diarrhoea?

It depends on how long your dog or cat has diarrhoea and vomiting and its severity. While some cases of diarrhoea vomiting in dogs or cats resolve quickly, others require immediate veterinary care. Knowing when to act is crucial for your pet’s health.

As previously mentioned, if your pet vomits or has soft stool once or maybe twice but is otherwise acting happy, energetic, and interested in food, then monitoring them at home and feeding them a bland meal may be enough to help them through.

Some of the following, however, suggest your pet should be seen by a vet (and not after waiting several days):

• More than one episode of vomiting or diarrhoea, particularly in a short period of time.

• You know or suspect toxin ingestion of any sort. The sooner you seek veterinary care the better - time is really of the essence for toxins.

• You see blood in the vomit or diarrhoea.

• Your pet is on chronic medication for any disease/disorder.

• Your pet is showing other clinical signs (lethargy, weakness, decreased appetite or lack of appetite, disorientation).

• Your pet shows symptoms on repeated days.

• Your pet seems to be in pain.

Thankfully, ManyPets customers have unlimited, fast, 24/7 vet advice at their fingertips with FirstVet. If you’re worried, you can access this and they can advise on whether you should see a vet straight away or if it’s safe to wait.

What should I do if a kitten or puppy has sickness and diarrhoea?

Things are more serious if your kitten or puppy has vomiting and diarrhoea as they become dehydrated very quickly.

Contact your vet immediately if the condition isn't a one-off, and offer them water to keep them hydrated.

For younger pets, the signs to call a vet are:

• Blood in the vomit or stool

• Frequent vomiting and diarrhoea

• Significant lethargy

• They can't keep down water

• Your kitten or puppy is very young

Monitor your puppy or kitten closely and don't put off going to the vet or an emergency vet if they're unwell. Dehydration is a serious issue in young pets.

How can I tell if my pet is dehydrated?

Symptoms of dehydration include:

• Lethargy

• Nausea

• Passing frequent, larger volumes of urine despite seeming dehydrated. This can be due to diabetes or kidney failure.

• Regular loss of fluid through things like diarrhoea, panting or vomiting

• Signs of pain

You must see a vet if you suspect dehydration.

How will a vet treat my pet for vomiting and diarrhoea?

Your vet will recommend therapy depending on their overall picture of your pet (their history, a physical examination, etc.).

For happy, bouncy and well-hydrated pets, the vet may suggest that monitoring or simple symptomatic therapy is warranted. This can include things like anti-nausea medications, probiotics, anti-diarrhoea medications, gastrointestinal-friendly diets, or even subcutaneous fluids.

Most online pharmacies can affordably fulfil and quickly dispense anti-nausea and anti-diarrhoea medication prescriptions.

For older pets or pets with other clinical changes, your vet will likely suggest further testing and more intensive therapies such as blood tests, faecal samples, imaging of the abdomen (x-rays, ultrasound), and intravenous fluids/medications.

How can I prevent diarrhoea and vomiting in cats and dogs?

Common preventative measures include:

Diet and nutrition

• Make sure your pet is getting a complete, balanced diet that focuses on their nutritional needs.

• Avoid giving them fatty, sugary foods, and slow down human foods like snacks.

• Don't give them bones - it can cause stomach upset, digestive system blockages and they're a choking hazard.

• Introduce diet changes slowly, and introduce new foods at a careful pace too.

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Hydration 

• Provide plenty of clean, fresh water.

• For pets that struggle to drink enough, like cats, try adding warm water to their food to make a gruel-like texture.

Preventative care

• Preventative pet care and veterinary attention can spot gastrointestinal issues early

• Make sure you regularly keep on top of intestinal parasite presentation with treatments like flea, tick and worm plans.

What breeds are prone to diarrhoea and vomiting?

Gastrointestinal issues tend to affect smaller dogs, especially toy breeds. Overall, these breeds can have gastrointestinal issues more than others:

• Bichon Frise

• Cavalier King Charles Spaniel

• Dachshund

• Maltese

• Miniature Poodles

• Miniature Schnauzers

• Pekingese

• Poodle

• Shetland Sheepdog

• Yorkshire Terrier

How pet insurance can help

Because pets can become dehydrated very quickly with persistent vomiting or diarrhoea, keeping pets for treatment in the vet hospital or out-of-hours vet is fairly common.

That can mean that treatment costs for diarrhoea and vomiting can be much higher than you’d expect.

The right pet insurance policy will give you peace of mind that you’ll be able to get your pet the treatment they need, when they need it, even if it’s out of hours or they need an overnight stay to get them hydrated, healthy and recovered.

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