Giardia In Dogs: Causes, Symptoms & Treatment

Giardia in dogs is a common and highly contagious parasitic infection that can cause a range of unpleasant symptoms, including diarrhea, vomiting, and weight loss. It’s important to be aware of the signs of giardia and take steps to prevent and treat the infection.

In this article, we’ll explore what giardia is, how it spreads, and what you can do to keep your furry friend naturally healthy and happy. Whether you’re a seasoned dog owner or a first-time pet parent, this guide will provide you with the information you need to protect your pup from this pesky parasite.

What Is Giardia?

Giardia is a single celled parasite that can infect dogs and cause a range of symptoms, including diarrhea, vomiting, and weight loss. This microscopic organism is found in contaminated water sources, such as lakes, rivers, and streams, and can be transmitted to dogs when they drink or swim in these areas.

Giardia can be present as a trophozoite that lives in the gut of infected animals or in the cystic stage that’s shed in the feces of infected dogs.

Giardia cysts can survive for several months in the environment, especially in water or damp conditions. If your dog comes across infected feces, giardia can cause an intestinal infection and transform to the trophozoite form. After about 5 to 12 days, an infected dog can pass giardia cysts in his stool.

Causes of Giardia In Dogs

According to the CDC, giardia survives longer in cold temperatures. If present in water temperatures below 50º F, giardia can live for 1 to 3 months but can survive only four days in water temperatures above 98º F.

In fact, it’s quite common for dogs to get giardia in the spring. As the snow melts, it can contain fecal residues that carry the giardia protozoa. If your dog drinks from melted snow puddles, they can pick up a giardia infection.

Here are some of the most common causes of giardia in dogs:

Contaminated Water Sources: This is the most common way dogs get a giardia infection. Puddles, ponds, lakes, or streams that have been contaminated with feces from infected animals are prime spots. When dogs drink or even just play in these waters, they can ingest the giardia parasites.

Dog Parks and Play Areas: These communal spaces can be hotspots for giardia, especially if they are frequented by many dogs. The parasite can be present in soil, grass, or surfaces contaminated with infected feces.

Contact with Infected Animals: Direct contact with an infected dog or other animals can also be a source. This includes sniffing or licking areas where an infected dog has defecated.

Contaminated Surfaces: Items like food and water bowls, toys, or bedding can harbor the parasite if they’ve been in contact with an infected animal.

Hiking Trails and Camping Sites: These outdoor areas can be risky if they’re frequented by wildlife or other dogs. Giardia cysts can be present in the soil or water sources in these locations.

It’s important to note that giardia is a zoonotic parasite, which means it can be transmitted from animals to humans. Always ensure your dog has access to clean, fresh water, especially when you’re out and about. And it’s a good idea to keep an eye on them to make sure they’re not drinking from or playing in suspicious water sources.

Symptoms of Giardia Infection

It’s important for dog owners to be aware of what to watch for, as giardia can be difficult to diagnose:

  1. Diarrhea: This is the most noticeable sign. The diarrhea might be soft, watery, or have a bit of mucus. Sometimes, it can even appear greenish. It’s not the nicest thing for your dog or for you, especially when it comes to cleaning up!
  2. Weight Loss: If your dog is eating normally but still losing weight, giardia could be the culprit. It can interfere with how nutrients are absorbed, leading to weight loss.
  3. Dehydration: Diarrhea can lead to dehydration, so keep an eye on how much water your dog is drinking. Signs of dehydration include dry gums or a general sense of lethargy.
  4. Poor Coat Condition: A dog’s coat often reflects their overall health. A dull or less shiny coat can be a sign of nutritional issues or just not feeling well, possibly due to giardia.
  5. Vomiting: While less common than diarrhea, some dogs with giardia might also experience vomiting.
  6. Excessive Gas: More gas than usual can be a sign of giardia, especially if it’s along with other symptoms.
  7. Stomach Discomfort: Your dog might seem more uncomfortable than usual, showing signs like belly pain or cramping.

Remember, some dogs with giardia don’t show any symptoms but can still spread the parasite. So, if you think giardia might be a concern, or if your dog is showing any of these signs, you might consider giardia infection. They can do diagnostic tests for giardia and suggest the best way to treat it.

Also, a strong immune system and healthy gut are key to preventing giardia, so healthy dogs and adult dogs are less likely to become infected.

Getting a Veterinary Opinion

One of the most challenging aspects of giardia infection is that it can be difficult to diagnose. The symptoms can be similar to other gastrointestinal issues, and the parasite itself is not always detectable in fecal samples. Giardia isn’t an easy parasite to detect, so it can live unnoticed inside your dog for a while.

If your think your dog might have giardia, contact your holistic vet and prepare a stool sample to have tested. Make sure the sample is no older than a day. If you can’t get it to your vet right away, store it in the fridge in an old pill bottle or glass jar.

Can Infected Dogs Give You Giardia?

Technically, giardia is a zoonotic disease, meaning it can infect humans. Fortunately, research says it’s not that easy for giardia to transfer between species. Even the CDC says the risk is small because dogs and people get different types of giardia.

If your dog has giardia, just take reasonable precautions:

  • Wash your hands regularly (especially after poop pick-up!)
  • Clean your dog’s bedding, toys, food and water bowls
  • Clean household surfaces
  • If you garden, wearing gloves to avoid contact with infected poop
  • Keep your environment dry (giardia likes damp conditions)

Veterinary Treatment for Giardia

There are three drugs that are commonly prescribed for dogs infected with giardia. None of them are approved by the FDA for animals and they carry some side effects you may want to know about, especially antibiotic-associated diarrhea and vomiting.

 Fenbendazole (Panacur): Side effects include facial swelling, hives, excess salivation and liver disease.

Metronidazole (Flagyl): Side effects include liver disease, allergic reactions and neurological issues including seizures.

Albendazole: Side effects include low energy, lower white blood cell production, and convulsions. Can also cause bone marrow suppression and liver disease.

Sometimes a combination of these drugs is subscribe with unknown interactions. There are some natural remedies that can be just as effective as veterinary medicine for giardia in dogs. The main benefit of natural remedies is they protect the dog’s intestines from the side effects of these drugs and can safely alleviate your dog’s symptoms without long-term risk.

Natural Remedies for Giardia in Dogs

Here are four herbs that can be used to help with infectious cysts, watery diarrhea and giardia in dogs and other pets:

Oregon Grape: is an effective natural antibiotic and liver tonic that can attack parasites. Give 10 drops of tincture per 20 pounds of body weight per day. If you prefer a glycerite (glycerin tincture instead of alcohol), give 25 drops per 20 lbs, as the herb doesn’t extract as well in glycerin.

For safety, only use Oregon grape for 7-10 days at a stretch. Don’t give Oregon grape to pregnant females or dogs with liver disease.

Cloves: work well against parasites like giardia. The oil in cloves is the key to their effectiveness.  One study found that essential oil of cloves can inhibit the growth of parasites. It also stated the essential oil can kill almost 50% of parasites in a “time-dependent manner.”

Give one clove per 10 pounds of body weight once every day. Or, mix a small pinch of clove powder in your dog’s food. Don’t give more than the recommended dose. Larger doses can be toxic, especially for small dogs.

Garlic: is a safe option to help boost your dog’s immune system. Allicin, one of the compounds in garlic, is effective against all parasites. You can release it by letting garlic sit for 15 minutes after chopping and peeling. 

Give up to 1/4 clove per 20 pounds of body weight, twice daily. Avoid giving garlic to your dog if he’s taking cyclosporine or blood thinners.

Goldenseal: The golden-yellow root of this plant that blooms in spring can treat a variety of conditions. Combined with garlic, it’s very effective against parasites like giardia. You can mix goldenseal as a dried powder into your dog’s food. Use 1 teaspoon per 20 pounds of your dog’s body weight.

You can also offer it to your dog as a tea, providing ¼ cup per 20 pounds per day. Or, give a tincture, 5 to 10 drops per 20 pounds about 2 to 3 times a day.

Herbal Combination for Giardiasis

This formula is recommended by herbalists Gregory L Tilford and Mary L Wulff. Combine the following tinctures:

  • 2 parts Oregon grape
  • 2 parts licorice
  • 2 parts cleavers
  • 1 part garlic

Low alcohol tinctures are best for this formula. If you can’t find them, dilute regular alcohol tinctures with an equal amount of water. You’ll need to double the dosage if you do this.

For low alcohol tincture, give ¼ tsp per 20 lbs of body weight, twice daily. Or … if you diluted regular alcohol tinctures as above, double the dose. Give the formula about one hour before food. You can give the mixture for up to 10 days. 

If you don’t want to make your own combination, you can also buy herbal combinations specifically formulated to treat giardia and other protozoal parasites.

Giardia in dogs can be a serious issue that requires attention and action from pet owners. By understanding the signs and symptoms of giardia, you can take steps to prevent and treat the infection.


What is giardia in dogs?

Giardia is a parasitic infection that affects the small intestine of dogs.

How do dogs get giardia?

Dogs can get giardia by drinking or swimming in contaminated water or by coming into contact with infected feces.

What are the symptoms of giardia in dogs?

Symptoms of giardia in dogs include diarrhea, vomiting, weight loss, and lethargy.

Is giardia in dogs contagious to humans?

Yes, giardia in dogs can be contagious to humans, especially those with weakened immune systems.