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Giardia in Dogs: 7 Things to Know

What is giardia in dogs and can you catch it from your pup? Get the scoop on seven things to know — from giardia symptoms to treatments.

Jackie Brown  |  Nov 8th 2017

Giardia infections (giardiasis) are a commonly diagnosed problem in puppies. They cause stinky diarrhea and are sometimes difficult to treat. Read on to learn everything you need to know about giardia in dogs to keep your pup — and yourself — healthy.

1. Giardia is not a worm.

A Golden Retriever puppy relaxing on the floor.

Puppies are especially susceptible to giardia. Photography ©appleping | Thinkstock.

Giardia is a parasite, but it’s not like a tapeworm or roundworm. Instead, it is a protozoal parasite, which means it’s a one-celled organism. Inside the body, giardia parasites attach themselves to the wall of your dog’s intestine, where they feed.

2. Giardia is mainly spread by wildlife and pets.

The most common route of transmission is drinking water contaminated by infected animals, including pet dogs and cats, wild mammals and birds. Dogs can also ingest giardia cysts by licking or sniffing places on the ground that are contaminated. Outside the body, giardia can survive for several months, especially in water or in places that are wet or damp. “Giardia is found in a lot of different locations,” says Tracey Jensen, DVM, Dipl. ABVP, founding partner of Wellington Veterinary Hospital in Wellington, Colorado. “Certainly, places where there is wildlife, particularly water fowl, or other dogs, so dog parks and places where there is standing water, can be areas where you can find quite a bit of giardia.”

3. Not all dogs infected with giardia will get sick.

“Most adult dogs are resistant to giardia,” Dr. Jensen states. “Most adult dogs have been exposed and will not become symptomatic. The dogs that really struggle and have trouble are the ones that have disease in their intestinal tract, like inflammatory bowel disease, or very young dogs. It’s not uncommon at all for puppies to have giardia.”

4. Giardia in dogs causes specific symptoms.

A sick, older dog lying on the floor.

Giardia symptoms include gastrointestinal upset. Photography ©stonena7 | Thinkstock.

Dogs infected with giardia will have gastrointestinal symptoms. “It will cause large volumes of mucous-y, very foul-smelling stool,” Dr. Jensen explains. “It can make it very difficult to housebreak a puppy because they have an urgency [to go that] they simply can’t overcome because of the giardia.”

5. Your vet can diagnose giardia with a simple test.

Giardia is identified by looking for cysts in the stool. If you can, bring a fresh stool sample with you to your appointment. If you forget, your vet can collect a sample in the hospital. He or she will view the sample under a microscope to look for giardia cysts.

6. Giardia in dogs is not always easy to get rid of.

Giardia is typically treated with two medications, fenbendazole and metronidazole, which are given for three to 10 days. It’s not uncommon to have to do more than one round of medication. “Giardia can be a little bit stubborn in terms of treatment, so get into a veterinarian right away if there are symptoms,” Dr. Jensen said. Your vet will want to recheck the fecal two to four weeks after treatment

7. Your dog can give you giardia.

Giardia is a zoonotic disease, which means it can pass between animals and humans. “Children are a bit more susceptible because they are not always good about washing their hands before they put them in their mouth,” Dr. Jensen says. “Practice good hygiene, making sure that you wash your hands before you eat or handle food. Keep the feces picked up in the yard as well to minimize exposure to other pets and people. Hose the area down to dilute out the number of organisms in any one spot and let it dry well.”

Tell us: Has your dog ever had giardia?

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