Search Menu
©Olesya Pogosskaya -

AKC is a participant in affiliate advertising programs designed to provide a means for sites to earn advertising fees by advertising and linking to If you purchase a product through this article, we may receive a portion of the sale.

Raising puppies is nerve-wracking. There are so many things to keep track of, from keeping up with vaccine schedules to removing socks and other foreign objects from your puppy’s mouth. As if that wasn’t enough to worry about, many puppies also experience something far less pleasant than chewing the occasional sock, and that’s puppy diarrhea.

What Causes Diarrhea in Puppies?

Diarrhea is one of those frustrating symptoms for owners because it could mean that your puppy has anything from a potentially lethal virus to simple indigestion. Many serious and minor puppy ailments list diarrhea as a symptom, making it hard for owners to determine what is serious and what is not.

Don’t panic. Despite the endless lists of horrifying diseases out there, there are six main causes of diarrhea in puppies that you need to know about:

  1. Diet change or food intolerance
  2. Bacterial infection
  3. Viral infection
  4. Ingestion of garbage, toxins, or foreign bodies
  5. Parasites
  6. Stress


There are many reasons why you might switch up your dog’s diet. Maybe your vet recommended a higher-quality brand of food, or your local store ran out of your puppy’s usual food. Regardless of the reason, even a simple change in diet can cause diarrhea in puppies.

Chocolate Labrador retriever puppy eating the spilled dog food on the floor outside his dish.
Antonio_Diaz/Getty Images Plus via Getty Images

Your current food could also be a problem. Sometimes puppies develop intolerance or sensitivity to certain foods or ingredients. If you suspect that your puppy has a food intolerance or sensitivity, talk to your vet about the best way to manage their diet and resolve the diarrhea.

Bacterial Infection

Puppies have more delicate immune systems than adult dogs, which makes them more susceptible to bacterial infections. Salmonella, E. coli, Clostridium, and other bacteria can cause puppy diarrhea. These diseases are serious and are usually accompanied by other symptoms, like bloody diarrhea, loss of appetite, fever, and vomiting.

Viral Infection

Perhaps the most worrying cause of puppy diarrhea is a viral infection. Parvovirus and distemper are both potentially fatal diseases that affect unvaccinated or partially vaccinated puppies. All viruses require medical attention from your veterinarian.


Puppies eat things that they are not supposed to. From garbage to poisonous plants, if your puppy can reach it, chances are they might try and eat it. Consuming garbage, especially garbage full of food, often leads to puppy diarrhea, and in some cases can cause blockages that require veterinary intervention to resolve.

Poisons and toxins also cause diarrhea. Call your vet or a local veterinary emergency center immediately if you suspect your puppy ate something potentially harmful.


Young puppies are prone to parasites. Whether they are born with parasites or pick them up from the environment, parasites like roundworms, hookworms, whipworms, coccidia, and giardia all cause diarrhea in puppies and all require veterinary attention.


Sometimes the reason behind puppy diarrhea is simple. Stress can cause diarrhea in dogs just like it does in humans, and puppyhood is certainly a stressful time. Your puppy is constantly meeting new people and exploring new things, and adjusting to the routine of your household is sometimes enough to trigger stress-related diarrhea by itself.

When to Call the Vet

With so many causes of puppy diarrhea out there, how do you know when to call the vet and when to wait it out? As a general rule, play it safe. Call your vet and explain your puppy’s symptoms, and let your vet decide if they think that your puppy needs to come in for a visit.

Most cases of puppy diarrhea are not severe. However, if your puppy has any of the following symptoms, call your vet immediately:

  • Bloody diarrhea
  • Black, tarry stools
  • Fever
  • Pale gums
  • Discomfort or pain
  • Vomiting
  • If you think your dog swallowed a foreign body or toxic substance
  • Diarrhea lasting more than one day

You should also call your vet if your puppy has not received all of their vaccinations and is having diarrhea. Parvovirus causes diarrhea in puppies and is a potentially lethal infection that requires immediate veterinary attention.

Treating Diarrhea in Puppies

The treatment for your puppy’s diarrhea depends on the cause. Mild diarrhea caused by stress or a dietary transition often clears up with the addition of a bland diet, although it is always a good idea to consult your veterinarian about at-home treatment options and to rule out anything more serious, especially if diarrhea continues for more than a few hours. Make sure you provide your puppy with plenty of fresh water, as even mild diarrhea is dehydrating.

Chinese Shar-Pei puppy being checked by a vet while a young boy watches.
pyotr021/Getty Images Plus via Getty Images

If your vet diagnoses your puppy with a bacterial or viral infection, you might have to hospitalize your puppy while they recover. Your vet might prescribe antibiotics to treat primary and secondary bacterial infections, and may also give your puppy intravenous fluids to keep them hydrated during their recovery.

Garbage ingestion might resolve on its own unless your dog ate something that caused an obstruction, but your vet may recommend switching to a bland diet until your puppy’s diarrhea clears up. Toxins and poisons require immediate veterinary attention, and the treatment varies greatly, depending on the toxin.

If your puppy has a parasite, the treatment regimen will depend on the kind of parasite and the severity of the parasite infection. Some parasites clear up with the administration of a medication, while others require a more in-depth approach.

Preventing Diarrhea in Puppies

Most cases of diarrhea in puppies are preventable. Here are some tips to help keep your puppy’s digestive system working smoothly:

  • Transition your puppy to a new diet slowly
  • If your puppy is in a kennel with other dogs, keep the facility clean and use the right disinfectants
  • Vaccinate your puppy at the appropriate ages and keep unvaccinated puppies away from unvaccinated dogs and public places like dog parks and kennels
  • Kennel your puppy when they are not supervised to prevent accidental ingestion of garbage and toxins
  • Talk to your vet about parasite prevention
  • Pick up after your dog

Diarrhea is your puppy’s way of letting you know that something is wrong. Whether the cause is an upset stomach or a viral infection, observing your puppy’s bowel movements is one of the best ways to monitor their health on a daily basis.

Lemonade pet insurance offers customizable policies for cats and dogs, so you can rest assured big-ticket vet bills won’t catch you by surprise. A base policy covers diagnostics, procedures, and medications for unexpected accidents and illnesses. Plus, you can opt for preventative care and add-ons, so you can tailor your pet’s perfect policy.

This article is intended solely as general guidance, and does not constitute health or other professional advice. Individual situations and applicable laws vary by jurisdiction, and you are encouraged to obtain appropriate advice from qualified professionals in the applicable jurisdictions. We make no representations or warranties concerning any course of action taken by any person following or otherwise using the information offered or provided in this article, including any such information associated with and provided in connection with third-party products, and we will not be liable for any direct, indirect, consequential, special, exemplary or other damages that may result, including but not limited to economic loss, injury, illness or death.

Related article: Vomiting in Dogs vs. Regurgitation: Everything You Need to Know
Get Your Free AKC eBook

Puppy Nutrition

Your puppy's lifelong health and happiness begins with you. Get it right from the start. This e-book provides valuable information on how good and sound nutrition habits will set your puppy on the right path.
*Turn off pop-up blocker to download
*Turn off pop-up blocker to download