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9 Reasons Why Your Dog Has Diarrhea At Night + 5 Tips (2023)

Why Does My Dog Have Diarrhea At Night

A worried dog parent is a common side-effect of diarrhea in dogs.

And diarrhea at night can be even more worrisome.

The time of bowel movement is puzzling too. 

Your dog suffering is the only thing you’re sure of.

It’s understandable if you feel helpless.

But knowing the problem can ease your worry.


Keep reading to discover:

  • 9 reasons for nocturnal diarrhea in dogs.
  • 5 useful tips to help you get through the night.
  • How each type of diarrhea arises and what you can do.
  • And so much more…

Why does my dog have diarrhea at night?

Your dog has diarrhea at night most likely because of a change in their diet, food allergies, and food intolerance. Other causes include intestinal parasites, bacterial or viral infections, garbage toxicosis, extraintestinal disorders, medicines, and stress.

9 reasons why your dog has diarrhea (only) at night

#1: Diet change

It’s something that baffles dog parents. Their dogs are fine during the day. They even go potty and make healthily formed piles of poop. 

Then night falls. And it’s a diarrhea marathon until the sun comes back up.

One cause of that could be diet change.

A dog’s diet may be changed for a number of reasons. Your little pup may be a young adult now. So you got them new age-appropriate kibble. 

Or there was a special occasion. So you treated them to a bit of table food.

Or perhaps there’s a new brand of dog food you tried out. I’ve fallen for some clever dog food marketing myself. 

But whatever your reason may be, the change may have shocked your dog’s stomach. 

It was receiving the exact same thing from the mouth for years. Then suddenly the menu is different.

It also happens in humans trying new cuisines. While it’s heaven to the tongue, the stomach has a different opinion. 

Change is seldom welcome. And abrupt change is even worse. Your dog’s stomach might just need time to adjust.

#2: Food allergies

According to FETCH, food allergies make up 10% of all dog allergy cases. It’s a genetic problem. And your dog may suffer from it.

The foods that often trigger allergic reactions in dogs are:

  • Soy.
  • Egg.
  • Fish.
  • Pork.
  • Beef.
  • Dairy.
  • Lamb.
  • Rabbit.
  • Wheat.
  • Chicken.

Dogs can have allergies to one or more of these foods. And the severity of the reactions will be different in each pooch. But in general, they include:

  • Diarrhea.
  • Vomiting.
  • Hair loss.
  • Sneezing.
  • Coughing.
  • Wheezing.
  • Flatulence.
  • Red inflamed skin.
  • Frequent scratching.
  • Chronic ear problems.

You’ve observed some of these symptoms in your dog. Along with them having diarrhea at night. Now you might be confused. There’ve been no recent changes to their diet. 

There’s an explanation for that.

Dogs can develop allergies later in life. Even to the food they’ve been eating for years. They might not have reacted before. But there’s a reaction now.  

And unfortunately, there’s no rapid test to confirm it. The only way is through an elimination diet. It’ll take time and patience.

You might also want to know: 21 Dog Breeds That Are Prone To Have Sensitive Stomachs

#3: Food intolerance

I know what you’re thinking.

“Didn’t we just discuss this?”

No, we didn’t. 

You’re not alone, though. It’s a common mistake. 

But a food allergy isn’t the same as food intolerance. Yes, they both have to do with food. And yes, they can both cause diarrhea. But there are important differences.

For one, food allergies are systemic. You’ll remember this from the previous section. They cause problems other than vomiting, diarrhea, and flatulence.

There can be respiratory issues. Such as coughing, wheezing, and sneezing. Or skin issues. Such as itchy, red inflamed skin, and ear infections.

But food intolerance is mostly limited to the stomach.

A dog with intolerance to certain foods will have diarrhea. And that’s about it. 

So if the diarrhea is coupled with respiratory or skin issues, you’re probably looking at an allergy. 

But while the two are different, they can be confirmed the same way. 

You may be feeding your dog different things. Especially if they’re a picky eater. Kibble alone won’t do.

So you’ll have to figure out what exactly they’re intolerant to. You can also use the elimination diet for this. 

But if it’s neither food allergies nor food intolerance, it could be…

#4: Intestinal parasites

Your Dog Has Diarrhea At Night Because Of Intestinal Parasites

This can be a bit of a sensitive topic. I feel you. 

The common image of dogs with parasites is of shelter dogs and strays. But a house dog with parasites? The poor parent gets mercilessly judged.

There’s only so much we can do, though. We have them up to date on their dewormer. We give them clean water and well-cooked food. 

But somehow, they can still wind up with parasites.

And these microscopic creatures can cause serious problems. Diarrhea tops the list.

So if your dog has cases of watery stools, consider intestinal parasites. Even if you’re a rabid OCD dog parent who’s particular about hygiene. 

It can still be parasites.

And according to the AKC, the main types that could be residents in your dog are:

  • Tapeworms. 
  • Whipworms.
  • Hookworms. 
  • Roundworms.

These can come from contaminated soil, food, or water. Or if you have a new puppy, they might’ve gotten it from their mother’s milk.

There’s no sure way of knowing where the parasites are from. But you can find out whether they’re really there.

A veterinarian will do a fecal exam. They’ll look at your dog’s stool sample under a microscope. And their observations will confirm if you’re dealing with parasites or not.

#5: Bacterial and viral infections

Diarrhea is a common symptom of bacterial and viral infections. 

Bacterial infections can even occur along with a parasitic infestation. That’s double the trouble. 

The bacteria that often cause infections in dogs are:

  • Salmonella. 
  • Clostridium. 
  • Campylobacter.

While the viruses include:

  • Rotavirus.
  • Distemper.
  • Parvovirus.
  • Herpesvirus. 
  • Coronavirus.

Diarrhea can be worse in bacterial infections. And even more severe in viral infections. Cases of diarrhea from diet change or food intolerance can be managed at home.

Diarrhea from bacterial and viral infections can’t.

Of course, the best course of action is always to see the vet. But it can be costly. And in some cases, a dog’s diarrhea problem gets resolved on its own. 

If you’ve experienced the latter, you’ll be even more reluctant to go.

But a bacterial or viral infection puts you in a race against time. And you just can’t afford to lose. 

#6: Garbage Toxicosis

Dogs are a handful. You can’t keep your eyes on them at all times. No matter what pet monitor companies tell you.

Some dogs have a disorder known as pica. They eat anything. Even items that are clearly not food.

And these pooches can harm more than your shoes. Their digestive systems can suffer the consequences. Like garbage toxicosis. 

It’s a result of dogs eating moldy or decaying food or material. Once these toxins get into the stomach, all hell breaks loose.

There’s a long list of symptoms. And diarrhea is on it.

Eating a bit of mold won’t cause severe problems. But you can’t be sure just how much mold your dog had. And garbage toxicosis can be fatal.

So it’s best to be safe and get them checked by a vet.

#7: Extraintestinal disorders

The cause of your dog’s diarrhea could be something they haven’t ingested. 

Diarrhea can be a symptom of other illnesses. According to PetMD, these include:

  • Cancer.
  • Pancreatitis.
  • Addison’s Disease.
  • Irritable Bowel Syndrome.

Their nature or mechanisms of action can affect your dog’s gastrointestinal tract. And stool in diarrhea due to these conditions often has blood as well.

If your dog has either of these illnesses, it could explain their diarrhea. But if there’s never been such a diagnosis, it might be a good time to get checked.

#8: Medicines

Yes, it’s odd. 

Medicines are supposed to help you. Or your doggo. But some are known to cause diarrhea. For instance, antibiotics.

Let me explain how these influence your dog’s body…

Your dog’s stomach is home to some good bacteria. They help prevent pathogens (organisms that cause disease) from colonizing it. 

They also do a bunch of other good things. Like, produce vitamins, for example.

But your dog may have a bacterial infection. It could be in the ear or somewhere on the skin. And they’ll need antibiotic therapy.

Good ole antibiotics will take care of the infection. But those infection-causing bacteria are not the only ones they’ll kill.

Antibiotics are very thorough. And they go the extra mile. That means getting rid of the good bacteria as well.

And without the good bacteria, there’s no balance. Pathogens are now free to come in. And then your dog has to “go”.


And again.

#9: Stress

Stress In Dogs

Stress in dogs can result in diarrhea. 

The body of a stressed pooch produces increased serotonin. This hormone is involved in digestion. It helps move food through the gastrointestinal tract.

But when your dog is stressed, too much serotonin can be produced in their gut. It causes spasms in the colon. This in turn produces bowel movements.

Your dog might be dealing with stressors. Or they might be having troubling nightmares. These cause an increase in serotonin. And so they have diarrhea at night.

If this is the case, it may be a relief. After all, it isn’t a vet emergency. But please remember that dogs are emotional creatures.

They’ll need more than just diapers. Love, care, and efforts in relieving their stress are far more important.

You can also check out: 19 Proven Ways To Calm Your Anxious Dog (How-To Guide)

What to do with a dog that has diarrhea at night? 5 tips

#1: Have your dog fast

Fasting is the standard procedure for diarrhea cases.

Don’t give your dog anything to eat for 12 to 24 hours. And give water only in small amounts. This will clear up their stomach and let it settle down. 

But only healthy adult dogs should be made to fast. Fasting could worsen the condition of other dogs.

If your dog isn’t able to fast, there’s another option.

#2: Try some home remedies

If your dog is still a pup, already a senior, or has a health condition, they can’t fast. 

But you won’t make anything better by giving them the same old food. That’s what might be causing diarrhea in the first place.

You can try out these home remedies instead:

  • Pumpkin.
  • Rice water.
  • Plain yogurt.
  • Plain white rice.
  • Boiled potatoes.
  • Cottage cheese.
  • Plain egg or chicken.
  • Specially-formulated dog foods.

These are safe and expert-recommended options. But they can’t beat consulting with a veterinarian for the best treatment.

#3: Give your dog probiotics

Probiotics can restore your dog’s normal digestive function. And they’re a great aid in many of the reasons I’ve outlined. 

Diet change, food intolerance, bacterial infection, antibiotic treatment, or stress. Probiotics can help.

You can get probiotics in capsules, tablets, and chews. Some formulations come as a paste in a syringe.

But if you have none of these available, you can always give your dog yogurt.

#4: Put your dog in diapers

You already know what to expect from your dog at night. So the most practical thing to do is prepare for it.

And you can’t get more practical in diarrhea cases than with a diaper.

Your dog may be well-trained. They know where they’re supposed to go potty. But sometimes, even the best dogs can’t make it to the door in time.

That’s where diapers come in.

You should put your dog in a diaper even several hours into a fast. Or even if they’ve taken any of the home remedies. Or if you’ve given them probiotics.

This way, accidents can be avoided. And your dog can keep a clean sleeping space. 

You might also be interested in: 9 Reasons Why Your Dog Suddenly Poops In The House (Again)

#5: Put your dog on an elimination diet

There’s only one way to confirm a food allergy or intolerance. And that’s through an elimination diet.

The idea is to completely change your dog’s diet. 

Put them on something they’ve never had before. And stick to it until their allergies are resolved. In this case, the allergic reaction is diarrhea.

Once that’s gone, slowly introduce some food from the old diet. Then wait and see which one causes a reaction again. It can take a few days or weeks. 

But you’ll get your confirmation. 

#BONUS: See a vet ASAP

In less severe cases, the other tips can get you through the night. But for more serious ones, no amount of plain egg and chicken can prolong your dog’s life.

Some bacterial infections can be pretty bad. While viral infections and toxicosis are even more unforgiving.

The best thing you can do is get your dog to a vet. There’ll be no reason for you to regret taking them. 

But you’ll most certainly have reason to regret not taking them.