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Giardia in Dogs

Learn about giardia in dogs.

Giardia is a type of parasite that affects the intestinal tract of dogs. It's a protozoan, which is a single-celled organism that isn't a bacteria, virus, or worm. It attaches itself to a dog's intestinal wall and feeds from it.

Signs of Giardia in Dogs

Dogs that are infected with only a few Giardia cysts might not show any signs. If they have a big cyst load, they might show some of the following signs:

  • Very soft to watery diarrhea that is often quite foul-smelling and usually contains mucus
  • Blood-tinged stools
  • Vomiting
  • Over time, weight loss can occur

How Do Dogs Get Giardia?

Dogs become infected with Giardia protozoa when they ingest cysts containing the infective form of the parasite. This happens most often when dogs drink from standing water sources. It's also common in situations where lots of dogs are present in the environment, like around kennels, grooming facilities, and dog parks.

Once the Giardia cysts are in a dog's intestines, they progress to a form of the parasite that feeds.

How Is Giardia in Dogs Diagnosed?

A fecal flotation test might reveal the presence of Giardia cysts, but they are quite tiny and difficult to find in a stool sample. Also, there may not be enough cysts present to see any on a small sample. When a typical fecal flotation test is performed at a veterinary clinic, a special liquid is mixed with the stool to help visualize parasite eggs better. For Giardia, a zinc sulfate solution can help increase the likelihood that cysts will be visible.

Special tests that look for proteins specific to Giardia cysts are also available. These tests may be done in a general veterinary clinic, or some fecal matter may be sent to a specialized laboratory to have them performed.

Sometimes, a diagnosis of Giardia infection is made based on signs, the prevalence of the parasite in the environment, and lack of a diagnosis of other parasites or illnesses.

How Is Giardia in Dogs Treated?

Panacur (fenbendazole) and metronidazole are the most common drugs used to treat Giardia in dogs. They must both be given at precise dosages for ten to fourteen days to be effective. Never give medications to your dog without your veterinarian's input.

Additionally, dogs with Giardia might need other treatments along with anti-Giardia drugs. If the dog has gotten dehydrated, can't stop vomiting, or has other parasites in addition to the Giardia, for instance, other medications and possibly fluid treatment will be necessary. If a dog has a chronic case of Giardia, a special, easy-to-digest diet might be required to help the inflamed intestines heal and resume proper function.

Is Giardia Zoonotic?

Humans can get Giardia from their pets, but it's a relatively rare occurrence. Still, if your dog is diagnosed with Giardia, use good hygiene, especially hand-washing after touching your dog or giving her medications. Also, clean the areas where your dog sleeps and eats thoroughly and often. Pick up and dispose of your dog's stool quickly, and use gloves when doing so.

Immune-compromised people, including very young, elderly, or sick people are at highest risk of contracting Giardia when their pet is affected by it.

How to Prevent Giardia in Your Dog

The best ways to prevent Giardia infection for your dog include:

  • Keeping your outside environment as cleaned up of stool as possible
  • Discouraging your dog from drinking out of standing water sources
  • Making sure you have a fecal sample checked at your veterinarian's office at least yearly or as often as your vet recommends for your area.

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