Diarrhea in cats and dogs

Diarrhea in our pets can be both a nuisance for you and a potentially serious issue for your pets. Severe cases can result in weight loss and dehydration. And while I won’t be all inclusive I wanted to discuss some of the most common causes for diarrhea, when it is serious enough to go to the vet, and what you can do to help.

Some cases of diarrhea may be self limiting and will resolve with time. If your pet is eating, has normal energy and is drinking enough to stay hydrated you may not need to rush your pet in to the vet. But honestly, sometimes my patients come in for treatment options not because they are at eminent risk of dehydration, but because they are having constant accidents in the house and the owners want a solution fast.

First lets start with puppies and kittens. There are some viruses that can cause severe diarrhea like parvovirus in dogs and panleukopenia (also a parvovirus) in cats. These animal will be SICK. Severe diarrhea, lethargy and dehydration. They should be seen by a veterinarian right away.

But another frequent cause of diarrhea in puppies and kittens is gastrointestinal parasites. Things like roundworms, coccidia, and giardia. Your veterinarian will need a fresh fecal sample to test for these parasites, but thankfully there are treatment options available. What many people don’t realize though is that not all parasites are treated the same and not all dewormers are the same. Some parasites, like whipworms, can have a long dormant period so you actually have to give an extra treatment 3 months after the first to be sure you get all of the parasites. And some of those parasites, like giardia, are microscopic. So when clients tell me they haven’t seen any worms in the stool that doesn’t mean much to me.

Most of our monthly heartworm preventatives will also help to prevent the recurrence of some of these parasites. Interceptor Plus is a great product which in addition to preventing heartworm disease, will also prevent infection from roundworms, hookworms, whipworms and tapeworms. And these are parasites your adult dogs can get if they are not on a preventative. Most parasites are spread through fecal-oral transmission which means areas where other dogs have pooped could have contaminated the ground or water.

Most indoor only adult cats will be at low risk for GI parasites but it is possible. So most vets will still recommend an annual test to check a fecal sample

In addition to viruses and parasites as a potential cause of diarrhea in dogs and cats, they can also get diarrhea from a diet change. This could be switching their food too quickly or just feeding a diet they don’t tolerate well. A true food allergy is rare, but there are instances where certain proteins or fat levels in the diet are just not digested easily. And if you have a labrador sometimes the diarrhea is just because they’ll eat anything.

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If your dog eats something off the ground or gets in to the trash, you may be cleaning up a second mess within the next 24 hours. If they are otherwise normal, no vomiting or lethargy, you may not need to go to the vet. Assuming no other health issues that would contraindicate this, I recommend a 24 hour fast to start. Leave water available of course, but don’t give any food or treats. Also, if you feed your pet twice a day, a 24 hour fast is really just skipping one meal. This gives the intestines a chance to rest and will usually result in a lack of diarrhea for a short period since they simply aren’t eating anything.

Then when it is time to feed them again I always recommend a bland diet. Most often this is cooked white rice with unseasoned boiled or baked chicken breast. If you don’t feed your dog chicken you could also try rice and lean ground beef. Just be sure to drain it well. You want to feed a really bland diet. There is no need to add in yogurt or pumpkin as I think the simpler the diet the better. I recommend a bland diet as their only food for 4-5 days. At this point your dogs diarrhea has hopefully resolved. If they are still having diarrhea after 5 days of a bland diet you should contact your veterinarian to get some help.

If they are diarrhea free then you can start slowly introducing their regular diet. This transition back to dog kibble should take about 5 days. On the first day offer about 80% chicken and rice and 20% of their kibble. Each day change this quantity by 20% back to the regular food as long as the diarrhea doesn’t return.

Cat’s also can benefit from a bland diet although I usually find it easier to prescribe a commercial bland diet as many cats are picky eaters. A newer diet which has proven to be very helpful for a lot of my patients is the Hill’s Prescription Gastrointestinal Biome diet. This diet does require veterinary approval so you should contact your veterinarian ahead of time to see if they would prescribe or recommend it.

The other thing which can be helpful for diarrhea is a probiotic. Purina’s Fortiflora is a good option and they have both a canine and feline version. Probiotics can take days or weeks to improve your pets soft poops so is a good option for more mild cases.

For some dogs, if their diarrhea is consistent or severe, they may need an antibiotic. Many cases of diarrhea in dogs are actually antibiotic responsive. So if your pet has blood in the feces, lethargy and loss of appetite your vet may want to treat with an antibiotic versus waiting to see if a bland diet will help.

Cats are less likely to have an antibiotic responsive diarrhea but many will improve with a diet change or probiotic.

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There are also many other causes of diarrhea and to arrive at a diagnosis your veterinarian may need to do more specialized testing. Inflammatory bowel disease (IBD), which can occur more frequently in cats as they get older, is characterized by chronic inflammation of the GI tract. These animals will have chronic, sometimes progressive diarrhea. They can also have other symptoms such as vomiting and weight loss. Diagnosis is best made by taking biopsies of the intestines, but many vets will start with bloodwork and abdominal ultrasound.

I also have many clients who do not wish to pursue surgery in their older pets so they will decline getting biopsies. In these cases I have a conversation about he potential risks of treating without a diagnosis. But if they are willing to accept these risks, which can include worsening disease, then I am willing to start treatment for suspected IBD.

When the diarrhea doesn’t seem to be from something simple (dietary indiscretion, parasites or stress) then I will recommend blood-work to be sure the diarrhea isn’t secondary to another issue such as liver or addison’s disease. There are also more specified blood tests we can run to look for maldigestion disorders. These tests will check for evidence of pancreatic disease and if your pet has low cobalomine or folate ,which are a couple of B Vitamins that are important in the ability of your pet to be able to digest their food appropriately.

This post is not meant to cover every potential cause of diarrhea and I did not want to delve deeply into many of the specific treatments we use. But it’s more to educate on ways you can protect your pet (such as using monthly heartworm prevention and avoiding diet changes which can trigger diarrhea) and how you can manage more mild cases at home. But if bland diet and probiotics aren’t helping, or if your pet is lethargic and anorexic then please schedule an appointment with your vet. We’re here to help you reach a diagnosis and get your pet started on the medications they may need.