Why Do Puppies Have Diarrhea At Night? (Causes & Solutions)

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If your puppy has nighttime diarrhea, you are probably trying very hard to figure out why and what you can do about it.

Let’s be honest. No one enjoys having – or dealing with – diarrhea. Not only is it messy, smelly, and gross, but it also leads us to worry about why it’s happening and how concerned we should be. And, when it’s your sweet little fur baby who is experiencing it, you feel helpless and bad for him as he tries hard to settle into his new life. Add to that it only seems to be happening at night, and now you are more worried than ever about what might be going on with him.

Night-time diarrhea in puppies is quite common and happens for a few different reasons. Your pup’s daytime diet, his level of anxiety and stress, and his current medical health will all result in his gut acting up in the evenings after his other bodily functions are starting to slow down.

Truth be told, diarrhea is kind of a blessing in disguise. I know, that sounds disgusting. But diarrhea, like a fever, tells you something is amiss in your body. Dogs are no exception. By having the evening liquid bowel movements, your dog’s digestive tract is telling you something is not going as it should. And now you get to figure out what and why.

I love dogs. I have always had them – more than I care to admit. But one thing that seems to never fail is they come to me experiencing gastrointestinal problems and no clear sign why. Let my research on this subject help you (and your pooch) get on track to sleep-filled nights and solid poop!

In this article

‍Why Do Puppies Have Diarrhea at Night?

Dogs can’t talk to us like people can. We usually don’t know our little pooch is feeling uncomfortable until something not-so-great happens, like diarrhea.

Unfortunately, diarrhea is not only unpleasant, but it also stalls your new pup's potty training progress. When your puppy has diarrhea, it’s hard for him to control his bowels. Also, diarrhea usually means that your pooch will need to go more often, and it will be more immediate. All of this means that potty training when your pup is having bowel issues will slow down the process.

1. Puppy’s Daytime Diet

Food can be tough on a puppy’s tummy, especially if they’ve recently been weaned or haven’t been fed adequate puppy food. Just like humans, certain things can really do a number on their inner digestive tract, and the results of that will often be seen at night.

When other systems start shutting down for sleep, your puppy’s digestive tract gets its chance to go into overdrive. All energy is focused in this area. It’s also common for your pup to have diarrhea at night because the sphincter muscles in their backside are relaxing as they sleep. Bottom line – they are no longer trying to hold everything back.

Try to keep your puppy on a good, high-quality diet. Even if their previous diet was less than ideal, if you can find out what they were being fed before they came to you, it will help if you can continue to feed them a bit of that and gradually wean them on to their new one.

2. Puppy’s Anxiety or Stress

Okay, not to be too graphic, but I think we’ve all had those moments when stress caused our bowels to get kind of wonky. As more studies are done, stress continues to be seen as a major factor in our sleep patterns, our mental and physical health, and how our bodies operate. Puppies are no exception to diarrhea and stress.

Whether you acquired your puppy from its momma, a shelter, or somewhere else, that little guy is dealing with a lot of change. You may be the best person on the planet for your new four-legged packmate, but it’s still stressful, scary, and hard for him to adjust.

Puppies (sadly) can’t talk to us. They can’t share what’s making them worried when they’re tired, if they are scared or if they don’t like sleeping alone in the dark. Instead, their stress may manifest in other ways, like not eating, not sleeping, whining, or irregular bowel movements.

I’ve even brought dogs home from the shelter who have not peed for over 72 hours! When I took them to the vet to find out what was wrong, they told me it was normal. Puppies are sometimes scared to pee because they don’t want to get yelled at. (Because maybe they have been before.)

3. Puppy’s Health

This is the big one. If your puppy is experiencing bouts of diarrhea at night because their food is different or because they are anxious or overwhelmed, that will all eventually pass. But, if your puppy has diarrhea for something medically related, it needs to be checked out by a professional.

Puppies – whether they are coming from their mother or an animal shelter – are very prone to intestinal worms. Whether they are roundworms, hookworms, or tapeworms, they are all equally unpleasant and will leave your new friend feeling poorly and having belly issues.

Unlike the above reasons for diarrhea, if your pup has worms, he will need to be seen by a vet. A puppy who has worms that are left untreated will get very sick and may die. The good news is, worms are relatively easy to treat. There are de-worming medicines that can be given orally by your vet that will kill these unpleasant parasites and help your new pup start feeling better shortly.

Worms are a serious problem for puppies and should be treated quickly if expected.

How Do I Help Alleviate My Puppy's Diarrhea at Night?

Puppies don’t have to live with diarrhea, and neither do you! Here are some quick and painless steps to rid your new packmate as quickly as possible from the unpleasant nighttime nastiness:

You Are What You Eat

It will take some time to get your puppy on a regular diet once he is with you. Depending on his age, maybe he just was weaned from his mom and is learning to deal with solid foods, or he’s been in a shelter or other home and has been eating one kind of food and you are introducing something else.

Regardless of why your doggy’s diet has probably changed and it’s going to take a while for it to sort itself out. If you can try and introduce new foods slowly, it will probably be best for your pup. If you can’t because it’s out of your control, just stay your course, give them the best quality food you can, and be patient while they (and their tummies) work through it.

If diarrhea seems to be worse at night, another option to consider would be to try and feed your furball a bit earlier in the evening. You don’t want them waking up in the middle of the night whining for lack of food, but if you can try and feed them a few hours before bedtime, it may give their bowels the needed time to empty before they hit the hay for the night.

Find Your Zen

Spend some time thinking through your pup’s daily schedule. Are there stressors you can alleviate or at least minimize, especially close to bedtime? Like with his diet, some of this may just be time – as he gets used to his new surroundings, so will his tummy.

But, if you can find ways to help him down the path of calming down close to bedtime, it may make his insides settle more quickly. Maybe a long play period or outside romp is not the best thing an hour or two before bed. Perhaps snuggle time late at night is easier on his insides than having a lot of new people come over to meet him after dinner or deciding you’re going to take him on a car ride right before bed.

Having a consistent schedule is going to help your puppy acclimate to your family faster. Making that schedule a priority before bed will help him feel more secure, and safer and will (hopefully) let his physical state calm down as much as his mental one.

Seek Help Sooner than Later

Finally, as with all things dog-related (especially puppies!), know when to seek help. As I said earlier, there are lots of reasons your new four-legged, floppy-eared friend is experiencing some tummy issues. But ruling out they are something more severe is important to your dog’s long-term health.

A veterinarian can do a simple, inexpensive, and non-invasive test to make sure your puppy doesn’t have worms. And if they do, treatment is immediate, and the problem should be gone within a week to ten days.

Make sure you give your puppy the tools they need for long and happy life from the get-go, and always involve your vet if you’re worried that their nighttime diarrhea isn’t something more serious than what you can handle (or clean up) alone.