Giardia Guide: How To Treat and Protect Your Dog

Diamond's Friends Pet Rescue
Jun 7
6 min read

If your dog has ever had a case of runny poop that just won’t go away or you’ve heard the word “Giardia” mentioned at the vet, you’re not alone. Giardia is one of the most common intestinal parasites in dogs. In fact, we regularly see it in dogs we pull from shelters.

Fortunately, if your dog has it, their prognosis is good! With medication from your vet and a little extra effort to keep things clean at home for a couple of weeks, your dog should make a full recovery.

Here’s the scoop on what Giardia is, how it spreads, and what you can do to keep your pup healthy.

What Is Giardia?

According to VCA, Giardia is a contagious intestinal infection caused by a microscopic parasite. In dogs, it primarily manifests as diarrhea.

What Is the Prognosis for Giardia?

The prognosis for most Giardia cases is good! So, if your dog has Giardia, don’t stress too much.

Most healthy dogs should recover fully with the right medication and care. However, geriatric, debilitated, or immunocompromised pups may be at risk of complications.

How Common Is Giardia?

Giardia is very common. Research done by Veterinary Parasitology reports that up to 15.2% of dogs have Giardia. However, according to PetMD, it can impact up to 45% of dogs in certain populations (i.e., kennels).

Learn More: Common Medical Ailments Your Shelter Dog May Come Home With

How Is Giardia Diagnosed?

Most veterinarians will use a stool sample to verify if your dog has Giardia because it’s too small to be seen by the naked eye.

Learn More: How To Choose a Veterinarian

How (And Where) Do Dogs Get Giardia?

Dogs get Giardia by swallowing the cysts. Cysts are shed in the poop of infected animals and can survive in the environment for several months.

Common ways dogs ingest these cysts include:

Contact with infected dogs or shared spaces (like kennels or dog parks)
Drinking contaminated water (like puddles, streams, or communal water bowls)
Licking contaminated fur or paws
Sniffing contaminated ground
Sniffing or eating or poop

The parasite thrives in damp or watery environments, so places with poor sanitation and high dog traffic are potential hotspots.

Learn More: Dog Parks 101

How Long Does It Take Dogs to Show Symptoms After Exposure?

After exposure, dogs start shedding Giardia within five to 12 days. However, symptoms may start prior to this.

It’s important to note that, according to VCA, some dogs may never show symptoms at all and still carry and shed the parasite.

What Are the Symptoms of Giardia?

The most common symptoms of Giardia include:

Diarrhea (this is the most common symptom)
Dehydration
Gas
Nausea and Vomiting
Stomach Pain

Some dogs may experience:

Decreased appetite
Lethargy
Weight loss

Learn More: At-Home Dog Health Checks

Can Giardia Cause Any Serious Health Risks for Dogs?

VCA reports that the most serious issue with Giardia is dehydration, which can be fatal in puppies or vulnerable adult dogs.

Some dog owners have also reported their pups experienced food allergies, food sensitivities, and even IBS symptoms after being diagnosed with Giardia.

How Is Giardia Treated?

Unfortunately, this ailment is not one you can just treat at home. Helping your dog recover from Giardia requires both veterinary treatment and at-home care.

Veterinary Treatment

Most vets will prescribe either Panacur (fenbenzadole) or Flagyl (metronidazole) to treat Giardia. Sometimes, they will prescribe both.

Generally, your pup will need to take these medications for three to ten days.

Retesting should be done a couple of weeks after completing treatment to make sure the infection is cleared. If it hasn’t, an additional round of medication will be needed, followed by another retest. You'll need to repeat this process until the infection clears.

In our experience, most cases clear with one round of treatment. However, we have had dogs who needed a couple of rounds of treatment before they tested negative.

At-Home Care

At home, you’ll want to:

Bathe your dog throughout treatment to remove any cysts in their fur
Clean your dog’s rear after pooping to reduce reinfection
Pick up poop immediately
Wash bedding, bowls, and toys frequently

Additionally, since dehydration is a concern with Giardia, make sure your dog is drinking enough water. If you feel like they aren’t properly hydrated, offering some wet food can help.

How Long Does Giardia Last?

It varies. These infections typically clear within one to two weeks with treatment. But reinfection is possible, which could delay your dog’s recovery time.

To minimize the amount of time your dog has Giardia, proper cleaning and disinfecting protocols are critical.

How Long Can Giardia Live on Surfaces?

Giardia can live in environments with direct sunlight for a few days. But, in cold water or soil, it's possible for Giardia to survive for several months.

Is Giardia Deadly?

The good news is that Giardia is usually not fatal to dogs. But, if your dog has an immature immune system or is immunocompromised, it can be life-threatening.

Is Giardia Contagious to Other Dogs?

Yes. Giardia is contagious to other dogs.

Is Giardia Contagious to Humans?

Yes, it can be. In fact, we know someone who got Giardia from a dog they were fostering through a different rescue.

VCA reports that Giardia genotype A can infect humans, dogs, and cats, while Genotype B can infect dogs and humans. That said, the CDC does report that dog-to-human transmission is not common.

How Long Is Giardia Contagious?

As long as a dog is still shedding cysts in their feces, they are potentially contagious to dogs and humans.

Is There a Vaccine for Giardia?

No. There is not currently a vaccine for Giardia.

While there was a Giardia vaccine developed in the past, it’s no longer on the market due to limited effectiveness.

How Can I Protect My Dog From Getting Giardia?

Here are a few steps you can take to protect your dog from getting Giardia, including:

Always picking up poop right away
Asking about regular fecal testing, especially if your dog goes to daycare, dog parks, or boarding facilities
Bathing your dog after Giardia treatment or muddy outings
Not letting your dog drink from puddles, streams, or communal bowls
Regularly washing food and water bowls, toys, bedding, and crates
Remove standing water in your yard

How Can I Protect Myself From Getting Giardia?

Personal hygiene and disinfecting your home are key strategies to protect yourself from getting Giardia from your dog.

Preventative measures like washing your hands after picking up poop or interacting with a Giardia-positive dog can be beneficial. Washing bedding and clothes regularly is also wise.

For extra protection, wearing disposable gloves when working with Giardia-positive dogs can provide extra peace of mind.

Final Thoughts

Giardia isn’t the most fun ailment for your dog (or you) to deal with, but it's not the end of the world. With awareness, treatment, and good hygiene, most dogs recover quickly.

If your pup starts showing signs, don’t panic. Call your vet so your dog can get tested and start treatment immediately if needed.

Disclaimer: This article is not intended as professional medical advice. It is based on personal experience and online research. Please consult with your veterinarian if you are concerned about your dog's health.

Sources

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