All About Giardia In Dogs

Giardia in dogs (full name is 'Giardiosis) is caused by tiny, single-cell internal parasites.

This disease is also know as 'Beaver Fever'.

The tiny organisms called 'Protozoa' attack your pet's gastrointestinal tract and can cause some serious trouble!

Dogs of all ages can catch 'Beaver Fever', but young puppies, senior dogs or dogs whose immune systems are weakened by stress, or another illness or health problem, are most at risk.

About Giardia In Dogs

The Giardia organisms occur all across the US (and in many other countries).

They're usually found in water that's been contaminated by the feces of infected animals - such as streams, creeks, ponds and lakes.

And Giardiasis isn't limited to dogs, many other species of animals, both domestic and wild (including Beavers!) can be infected...

.... even humans can get it, but usually the type of Giardiasis that affects dogs is not easily transmitted to people.

Dogs and other animals often ingest Giardia protozoa by drinking the infected water or playing/swimming in it.

People tend to pick it up from swimming, or occasionally by drinking from water supplies that have become contaminated by sewage.

Once inside the host's body, Giardia attach themselves to the inside of the intestinal walls, and develop into cysts which multiply rapidly, and may cause irritation, pain, interrupt the way your pup's body absorbs nutrients from his food and generally make life miserable.

The life-cycle of these organisms causes the cysts to be shed inside the gastrointestinal tract and excreted in your pup's feces. They may then be ingested by another animal and start all over again in a new host.

Many healthy puppies or older dogs can be 'carriers' for this disease - this means that they have Giardia organisms in their bodies, but don't get sick - but even though they're not affected, they do pose a risk to other animals/pets.

Over time, the infestation does cause damage and symptoms eventually appear, but even while they seem perfectly healthy, they are a risk to other pets and animals who can catch the disease from their infected stools.

Giardia Symptoms

Symptoms of Giardiasis in dogs aren't always obvious. 'Carriers' of this infection are 'asymptomatic', which means that they don't show any outward signs of having the disease at first.

Over time they will start to have digestive upsets, they might lose weight, have a dry/dull coat, pass pale colored/smelly/greasy stools, get dehydrated or seem excessively tired or weak.

The most common symptom is of giardia in puppies is diarrhea.

This can be Acute (meaning it can come on suddenly and be severe), or Chronic (meaning the bouts of diarrhea are intermittent, and might even come and go over several weeks. They're also less severe).

The diarrhea that's associated with Giardia in dogs is usually very watery and has a strong and very unpleasant smell! It might be pale, or foamy, or contain mucus and/or streaks of blood.

There are other symptoms which might accompany the diarrhea, these include:

  • Vomiting
  • Loss of appetite
  • Weight loss
  • Lethargy and or weakness
  • Excessive gas
  • Dehydration
  • Fever


Diarrhea in puppies can also be a symptoms of other illnesses and conditions. 

Some minor, but others very serious!

Canine Parvovirus is one of the most common causes of severe puppy diarrhea.

It's a VERY dangerous illness which can kill your puppy within days (sometimes within 24 hours).

Parvo is the #1 risk to your puppy's health, and early detection and treatment are the only chance he will have of survival.

If your puppy has repeated watery diarrhea, get him examined by your vet immediately to rule out Parvo.

Canine Giardia Treatment

Your veterinarian can test for Giardiasis by testing a sample of your pup's poop for the tell-tale Giardia cysts that have been shed.

But because these cysts are very tiny, and not shed constantly, it's possible to get a negative result even in animals who actually have the disease.

If your pup has the right symptoms, and has possibly been exposed to Giardia, then your vet may test your pup's stools several times over a period of a few days.

There are also blood tests now available to test for Giardia in dogs, and these are far more accurate than testing stool samples.

Luckily, treatment is usually fairly straightforward. You vet will probably prescribe an antiparasitic medication for you to give your pup for about a week. The most common medication used to treat Giardia is Metronidazole (known as Flagyl) and it works well.

If by any chance your pup's infestation doesn't respond to this, then there are other possible medications your vet can try, including Fenbendazole (Panacur).

Metronidazole shouldn't be given to dogs who are pregnant as it could cause birth defects in the unborn puppies. So, make sure to let your vet know if your dog is diagnosed with canine giardia and could be pregnant.

The bad news is that these treatments don't always totally eliminate the Giardia protozoa first time around.

This means that although your pup is feeling much better, he could still carry the disease and risk passing it on to other animals, or have a relapse later on.

So, if your puppy has been treated for Giardiosis, and his symptoms disappear, just be aware that it could show up again later on - and take him straight back to your vet if symptoms do reappear.

There are many different strains of Giardiosis, and just because your puppy has had the disease once, it doesn't rule out the possibility that he could catch a different strain another time....

.... but at least now you will be familiar with the symptoms, and able to recognize the problem quickly.

Giardia in dogs are very hardy little parasites, and eliminating them from your environment can be a challenge.

A 1:10 or even 1:5 bleach/water solution is usually effective. So are Lysol, and Quaternary ammonium disinfectants, which are antibacterial cleansers usually used by farmers for bacteria control.

Because there's a small risk of Giardiosis being transmitted to humans, excellent personal hygiene is highly recommended if your pup is infected!

If you notice any flu-like symptoms, or vomiting/diarrhea in yourself or other members of your family, visit your doctor.

Related Pages......

› Giardia In Dogs

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