Giardia in Dogs: Symptoms, Causes & Treatments

Giardia in Dogs: Symptoms, Causes & Treatments

Giardia is an intestinal infection that causes illnesses in dogs. It’s a common cause of diarrhea and dehydration — and it can even infect humans. What are the symptoms and causes of giardia in dogs? What treatments are effective against it?

We’ll answer those questions and more in this article. We’ll also provide tips on how to prevent giardia effectively. Read on!

What is Giardia in Dogs?

Giardia — also known as giardiasis — is a protozoal parasite that causes intestinal infections in dogs. Some strains can also affect humans, and they can be spread without any obvious signs.

The parasite attacks your dog’s intestinal walls, causing foul-smelling diarrhea. Other signs your pet may have giardia include:

  • Blood in feces
  • Poor coat condition
  • Dehydration

Let’s dive deeper into these symptoms.

Giardia Symptoms in Dogs

The most common signs of giardia in dogs are foul-smelling and watery diarrhea. The color might be yellow or red; you might also find mucus or blood in the feces.

Because of diarrhea, your dog may experience weight loss and dehydration. If left unchecked, giardia can cause other symptoms such as lethargy, appetite loss, and vomiting.

You may also observe behavioral changes in your dog, such as increased thirst and reluctance to play.

The tricky part is this: most dogs don’t typically show signs of giardia until it’s serious. But how do dogs get infected with giardia in the first place?

How Do Dogs Get Giardia?

Is giardia contagious in dogs? Dogs get giardia by ingesting food, licking food, and sniffing the parasite cysts from contaminated grounds or water. In other words, infection is easy — even walking in a contaminated area can trigger an infection.

The most common places for infection include densely populated areas such as kennels, pet shops, and animal shelters.

To prevent transmission among dogs, provide them with separate defecating areas. This lowers the risk of healthy dogs picking up giardia cysts from infected ones.

After your dog defecates, wiping their bottoms is advisable since it prevents dogs from grooming each other. Dispose of feces promptly and wash your hands after being in contact with an infected dog.

How Long is Giardia Contagious in Dogs?

The incubation period usually lasts for 1 to 14 days but can take as long as three weeks. As long as parasites are in the dog’s poop, the contagion will remain.

And even if symptoms have been resolved, shredding giardia cysts in infected dogs can take up to several weeks. That’s why preventative measures are important — more on this later.

Is Giardia In Dogs Contagious To Humans?

In rare cases, yes: you can also get giardia. Hand-to-mouth infections can happen easily with contaminated water, soil, or surfaces. If you sniff dirt where giardia parasites are present, you may also get infected.

Diagnosing Giardia In Dogs 

Again, diagnosing giardia in dogs can be tricky because symptoms aren’t always obvious.

Physical examinations are a good start, however. Your vet will also check the complete health history of your dogs to determine possible exposure to contaminated areas.

Other tests can also lead to more accurate diagnosis. These tests include:

  • Direct smear
  • Stool sampling to detect first-stage trophozoites
  • Fecal floatation to detect tiny cysts

Fecal ELISA and direct fluorescent antibody assay are also great. If your dog is unvaccinated, your vet may also request CBC and Parvovirus testing to rule out parvo.

How Long Does Giardia Last in Dogs?

This depends on your dog’s overall health and the severity of the infection. If detected early, giardia can be cured within five to eight days after medication. But it could last for months if not treated early.

Age can also play a role: puppies may take time to recover because their immune systems are still developing. Old dogs can also have difficulty recovering if they have other age- and health-related issues.

To ensure your dog recovers fast from giardia, closely follow your vet’s treatment protocol. Make sure your dog’s surroundings are clean and free of contaminants. On top of that, keep your pet in a calm and stress-free environment.

Treatment for Giardia in Dogs

The treatment of giardia in dogs includes medication and home care options:

Medication Options

Most vets prescribe medication for giardia in dogs. The most common medications include fenbendazole and metronidazole, which can be combined when necessary.

If your dog is dehydrated, fluids and nutritional support are required. These help with combating weight loss, too. On top of that, vets may also advise you to bathe your pet with shampoo that removes fecal matter from your dog’s fur.

Depending on the severity of the infection, follow-up tests are sometimes necessary. Retesting should be done for two to four weeks after treatment.

Homecare Options

Homecare treatments are recommended after acquiring medications for your dog.

  • Keep your dog’s environment clean and dry, and prepare a quiet and comfortable place for your pet. Use pet-safe disinfectants when cleaning.
  • Follow any at-home medication your vet prescribes. Even if symptoms improve, ensure your dog completes the medication.
  • For severe dehydration, giving electrolytes is recommended. This, combined with providing fresh and clean water to your dog, will prevent further dehydration and diarrhea.

You may also consult your vet about comprehensive health supplements for dogs to boost their health while in recovery mode.

Preventative Measures

Once your dog or dogs are free of giardia, remember that prevention is better than cure. This involves proper hygiene and vet care.

Always provide fresh water and separate food bowls to your dogs, and bathe them regularly to remove any fecal matter on their coats.

If possible, limit their access to bodies of water such as ponds and creeks. This helps your dogs avoid contaminated water.

Your vet may also require routine check-ups and vaccinations — follow them.


Overall, giardia is an infection that’s easy to get and hard to detect. However, it’s also treatable through medication and at home. Proper hygiene, clean surroundings, and early detection are enough to treat it and prevent re-infection.

If you’re looking for effective supplements to help with giardia in dogs, check out Under The Weather Pet’s selection of diet products. Our premium digestive supplements for dogs include anti-diarrhea liquid, probiotics, and more.

Every Sale Supports a Shelter Pet. Learn More. 

Created in Vermont. Learn More.

If you suspect your pet is sick, call your vet immediately. For health-related questions, always consult your veterinarian, as they have examined your pet, know the pet's health history, and can make the best recommendations for your pet.