Why Does My Puppy Have Diarrhea? How To Know When It’s An Issue

One of the most common problems that new puppy owners may experience is diarrhea. This is no fun for anyone, but especially the puppy. I have over 20 years experience treating puppy diarrhea as a veterinarian and I’m going to share some of that knowledge with you so you can help your little one.

What Causes Diarrhea In A Puppy?

Change In Diet

Many owners will change their puppy’s food when they first bring them home. It’s possible that the puppy food that the breeder is feeding is difficult to find where the owner lives and a diet change is inevitable. It might be that the food is too expensive or that the owner has a preference in what they like to feed their dogs.

Any changes in diet should (in a perfect world) be done over a 5-7 day period where you switch out a little of the old food with the new food every day until the food is completely switched over by day 5-7.

Intestinal Parasites

There are areas of the country where intestinal parasites are more common than others (such as the South), but any puppy can acquire a parasite that causes diarrhea. Most folks jump right to thinking about worms and those can include roundworms, whipworms, and hookworms.

However, here in Colorado we also have microscopic parasites such as coccidia and giardia that commonly cause diarrhea in both adult dogs and puppies.

Eating Things They Shouldn’t

Puppies will put anything in their mouth. Just like a little 18-month old human child. It can be nearly impossible to prevent your puppy from picking up things in their environment when they are so close to the ground.

Don’t add to the problem by giving them new snacks that they’ve never tried when they first come to your home. Too much change too quickly can cause diarrhea.

Also, as much as you want to, try not to give them any people food when they’re puppies. It’s so tempting but also likely to cause soft stool to introduce something so different from their normal food.

Viral Infections

The big concern with a viral infection will be Parvovirus. Ever since it appeared in the early 1980’s the general public has been very aware of how dangerous Parvo is and why they don’t want their puppy to ever get it.

How can you tell it’s Parvo? This virus usually causes the intestines to begin shedding so many intestinal cells that the smell or sight of blood in stool/vomit is evident. If there’s not enough blood yet to discolor the stool you still may be able to smell the iron scent that’s usually present.

Parvo will also cause most puppies to become lethargic quickly and they seem to go downhill rapidly. If your pup’s diarrhea is accompanied by lethargy, they need to be seen by a vet immediately.

However, there are a few other viruses that can cause diarrhea that are “self-limiting.” That means that the pup has some diarrhea over the course of a day or two and then it goes away on its own. There is a marked difference between this and Parvo.

Dietary Intolerance

Some puppies have problems with certain foods. There isn’t any one particular food that is hard on puppies. They just can’t handle the mix of ingredients or the specific ingredients themselves. It doesn’t mean that there is a problem with the food or the dog.

Many Times It’s A Combination

Puppy diarrhea can sometimes be frustrating because it doesn’t always go away after a diet change or after medication is given by the vet for a specific parasite. I’ve had to, at times, try 3-4 different things before we were able to get the stool back to normal.

What Medications Do Vets Use To Treat Diarrhea

Treating diarrhea in a puppy can involve many different treatments/medications. From anti-parasitic medications to antibiotics, each case of diarrhea is different from the next. There is no one universal treatment for puppy diarrhea.

The point I’m trying to make is that don’t always expect the first treatment choice to work with your puppy’s diarrhea. Also, if you try something at home and it works (or doesn’t), let your vet know. I know I’m always collecting information about what works for some people (or doesn’t) and I’ve been a vet for over 2 decades.

How Can I Treat The Diarrhea At Home?

If your puppy is acting normal and it’s a weekend (and you don’t want to go the ER), you can try certain things to try and help them stay healthy and get their stool back to normal.

  • If you’ve recently changed your dog’s diet, put them back on the original diet if you can. Once the soft stool is back to normal, you can try a slower transition to see if that will help.
  • If diarrhea is accompanied by vomiting, take them to the vet right away. It doesn’t take long for a puppy to get really sick from dehydration and electrolyte imbalances.
  • If the pup is acting totally normal and the stool is just a little soft, give it a day to see what happens.
  • If the stool is actually runny/watery, you can always try a bland diet for a day or two as long as the pup is acting normal. Bland diets can include white rice, boiled chicken/hamburger, and even scrambled eggs. I usually recommend a 3:1 (carb : protein) mix with a smaller volume than you normally feed. Instead of feeding them 2-3 times per day, you’re feeding a bland diet that contains less calories and volume 4-5 times per day.

When To Call The Vet About Your Puppy’s Diarrhea

  • At any time if you’re worried
  • When it’s also accompanied by vomiting
  • When your puppy stops eating
  • When they get lethargic
  • When the diarrhea has gone on for more than two days, even if your pup is acting normal
  • Again, any time you’re worried