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why does puppy have diarrhea at night

Why Does My Puppy Have Diarrhea at Night? What Should I Do?

Puppies are quite vulnerable to illness and infection, so when they get nighttime diarrhea, it’s hard to know the cause. We look at the possibllities and treatments.

Raising puppies can sometimes be nerve-wracking, especially for novice puppy owners. There are many things to keep track of, such as keeping up with vaccine schedules and removing foreign objects from your puppy’s mouth! As if this is not enough to worry about, many puppies suffer something far less pleasant than chewing on inappropriate things, and that is diarrhea at night. This isn’t uncommon for puppies, but it may be a sign of something severe. So why does your puppy have diarrhea at night?

Reasons your puppy may have diarrhea at night inched recent dietary changes, food intolerance and allergy, illness or disease, medication, stress, and parasites. If your puppy continues to experience diarrhea frequently or it gets worse, call your vet.

Let’s look further at why puppies have diarrhea at night, what to do about it, and when it’s time to call a vet.

Why Does My Puppy Have Diarrhea at Night?

Diarrhea is a frustrating symptom for puppy owners because it can mean that your puppy has anything from simple indigestion to a serious illness. There is a wide range of puppy ailments, both minor and serious, for which diarrhea is a symptom. This makes it hard for owners to determine whether they should be alarmed or not.

So, what may be the reason behind your puppy having diarrhea at night?

Dietary changes

A sudden change in your puppy’s food can cause nighttime diarrhea. Whether a company stops making the food you’ve been feeding your puppy, or you can no longer afford the same expensive brand, making a sudden food change can be tough on your puppy’s stomach.

Another thing worth noting is that transitioning from puppy food to adult food can have an impact on your pup’s digestive system. Changing your pup’s diet suddenly isn’t feasible since its stomach and intestines need time to adapt to absorbing new nutrients.

Vets advise a slow introduction to a new food to enable your pup to adjust so that it doesn’t wake up through the night with diarrhea. You should mix the new food with the old food, introducing it slowly into your pup’s diet. Gradually increase the amount of the new diet in the mix until it becomes what you majorly feed your pup.


Dogs are emotional beings, and their body responds to stress in several ways. If your pup is anxious, their digestive system may respond unfavorably, much as a human’s does. The same can happen if your dog feels lonely or neglected. Your pup may experience emotional distress, and adjusting to this can sometimes be enough to trigger nighttime stress-related diarrhea.

Illness or disease

Underlying diseases and illnesses may be behind your pup’s nighttime diarrhea. Some of these conditions can be serious, and others not so much.

It may be something as relatively simple as Colitis or Inflammatory Bowel Syndrome causing diarrhea in your dog. It could also be something as serious and life-threatening as cancer tumors in your pup’s intestinal tract.


Nighttime diarrhea in your dog can be a sign of something serious such as intestinal parasites. If your pup has been drinking water from a contaminated source, it may have contracted parasites like hookworms, roundworms, giardia, or coccidia. Young pups with weakened immune systems are particularly vulnerable.

Food Intolerance and Allergy

Just like humans, dogs suffer from food allergies and intolerance. No matter the breed, your pup may be sensitive to food rich in gluten, fat, or dairy. This sensitivity may lead to diarrhea. Dogs can also be allergic to certain proteins, like chicken or lamb, for example, which can cause diarrhea.

If your puppy has access to people foods, there are a number that are toxic to dogs. Check out this list of people foods toxic to dogs to see if your pup may be ingesting one of these foods.


If your dog starts on some medication such as dewormers or antibiotics, you can expect them to have diarrhea for a few nights. This is considered normal, and your vet will usually warn you about this before prescribing medication to your pup. 

puppy diarrhea at night

Is It Normal for Puppies To Have Diarrhea?

Diarrhea is normal in puppies and it isn’t unusual for them to experience one or two mild episodes. Even a healthy puppy, at some point, will experience diarrhea. This is because puppies do not have fully functional immune systems. They are therefore more sensitive to changes and potential sources of infection than adult dogs.

Mild cases of diarrhea in puppies may go away fast on their own, but other cases can point to a more serious problem. So even though it’s normal for puppies to have diarrhea, you should keep an eye on your pup to make sure it isn’t something serious.

Another factor to consider when a puppy is having diarrhea at night is that puppies poop more frequently than adult dogs. And because a puppy is always inside at night, you are more likely to discover the diarrhea (either by their wake-up whine to go out or a mess on the floor) than during the day.

So your dog may not just be having diarrhea at night; you could just more aware of it then as opposed to your pup eliminating in a garden bed that you don’t notice, for instance.

When Should I Worry About Puppy Diarrhea?

As frightening as your puppy having diarrhea is, it shouldn’t immediately cause a trip to the vet. Even in healthy dogs, diarrhea happens once in a while, and it’s most prevalent at night. However, there are times when it could be something serious.

You should worry about the issue when you notice the diarrhea isn’t stopping or it’s getting worse. If the episodes become frequent each night, then a trip to the vet should be in order. 

Also, if you notice your pup’s appetite changing, that they are drinking more than normal, or is generally frantic and uncomfortable, then it may point to issues with illness, poison, or something else. Anytime diarrhea in your pup is paired with some other symptom, consider taking them to the vet.

How Do I Stop My Puppy From Having Diarrhea?

You can prevent your puppy from having diarrhea by:

  • Getting medication for your dog that doesn’t affect his gastrointestinal tract causing him diarrhea. Your vet should be able to advise you on this.
  • Avoid switching your dog’s diet all of a sudden. Introduce a new diet slowly to allow your dog to adjust.
  • Ensure your dog is emotionally happy and doesn’t feel stressed out and neglected.
  • Carry out regular deworming to kill parasites that may cause diarrhea.
  • Feed your dog food that is appropriate for its breed to prevent food allergies and intolerances.

What Do I Feed a Puppy With Diarrhea?

First, you should introduce fasting for your puppy experiencing diarrhea. Withholding food for 12-24 hours and providing water in small amounts frequently can help clear out the cause and allow your pup’s digestive tract to settle. 

Before embarking on this, make sure your puppy is healthy enough to handle it and consult your vet to see if it’s a good idea to do so.

After a fast, you should introduce food slowly, and you should start with binders to normalize stool consistency. Opt for bland and easily digestible foods like rice water, white rice, canned pumpkin, boiled potatoes without skin, cottage cheese, yogurt, cooked macaroni or oatmeal, high protein foods like eggs or chicken, herbs like fennel, specially formulated dog foods for the stomach problems, and probiotics.

Final Thoughts

You can read more about treating dogs with gastrointestinal issues in our article How to Treat Upset Stomachs in Dogs. Although nighttime diarrhea is normal and typically nothing to worry about. If you suspect a serious issue, you should take your puppy to the vet for a check-up.

Superb Dog Editor

Superb Dog Editor