Dog Parvo Symptoms

Learning more about parvo symptoms in puppies and dogs is essential as this viral infection can cause serious health problems, even death, to our dogs. Common symptoms of intestinal parvo include diarrhea, vomiting, dehydration, appetite loss, and lethargy.

Canine parvovirus is an extremely serious disease with a high fatality rate. It can affect dogs of all ages but young puppies are particularly vulnerable because of their still immature immune systems.

All dog parents should learn about the various parvo symptoms so that timely diagnosis and treatment can be given to the dogs in the event that such signs and symptoms are observed.

This page takes a look at the various clinical symptoms exhibited by puppies and dogs with parvo.

Intestinal Parvovirus Symptoms

Symptoms of Parvo Parvo symptoms in puppies and dogs come in different degree of severity, depending on various factors, such as the age and the overall health of the dog.

Many adult dogs exposed to the virus show very few clinical symptoms, if any at all. Young puppies (12 weeks or younger) are the most vulnerable. In fact, the majority of cases of disease are seen in dogs less than 6 months of age.

The symptoms described below are those of the more common dog parvovirus - the intestinal parvo. These symptoms may not appear in the order as listed below. Every dog is slightly different.

Usually, the onset of these clinical symptoms is rather sudden, often 12 hours or less.


As the parvovirus attacks intestinal cells, GI tract problems are common parvo symptoms.

One such problem is vomiting - usually uncontrollably. The dog will continue to heave and throw up yellow bile even after the stomach has been emptied.


Another typical symptom of parvo is diarrhea.

The stools have a very distinct, foul odor. At the beginning, the stool is yellowish or greenish looking. It will then turn into a dark-brown runny stool, which actually is old blood from the small intestine.


As the puppy continues to vomit and have diarrhea, he can become seriously dehydrated very quickly, losing a lot of vital electrolytes, such as potassium.

Potassium is responsible for nerve conduction; it regulates the heart beat and muscle contraction.

As you can see, low potassium levels can lead to extreme shock to the dog's system. Some dogs die from cardiac arrest simply because the potassium level is too low.

Thus, dehydration is often fatal and in fact is the main cause of death for dogs with parvo. A dog with parvo may die from dehydration in about 48-72 hours after showing symptoms of vomiting and diarrhea.

Therefore, it is extremely important to get your pup early treatment at a vet if he shows parvo symptoms to prevent dehydration.

Click here to see how to check for dehydration in dogs.


A puppy with parvo may appear lethargic. He is reluctant to play and seems to be sleeping or lying around a lot more.

There are several reasons why a puppy with parvo is lethargic. The main reasons are:

  • Weakened body organs, such as the heart, liver, and kidneys
  • Low blood sugar
  • Dehydration

Appetite Loss

As the intestinal lining is destroyed by the parvovirus, a puppy with parvo will lose his appetite and show no interest in food.

Other Possible Parvo Symptoms

In severe cases of dog parvo, the dog may develop a fever (sometimes as high as 106°F). Also, the white blood cell counts will become lower.

A dog with parvo may also appear depressed and lose interest in even his favorite activities and games.

Vomiting but No Stools

Sometimes a dog with parvo vomits but has no stools. This may be due to one of the following reasons:

  • The dog may have both Parvo and worms.
  • The dog is severely dehydrated. Test for dehydration and try to rehydrate the dog.
  • The dog's intestinal tract lining is swollen, which can be due to various reasons. This condition can become serious: if the puppy is straining to pass a stool, this can be hard on the heart, which can be weakened by the presence of the parvo virus.

If your dog does not produce any stools in 24 hours, you should take him to your veterinarian to check for blockage, as a blockage is life threatening.

Corgi Puppy

General Information and Treatment of Parvo in Puppies

Also visit this page for more general information on parvovirus in puppies and dogs.

For treatment, click here.