Giardia is found all around the world and typically infects dogs, cats and humans. It is a single-celled parasite that is found in 2 forms, a fragile form known as a trophozoite and a hardier cystic form. It is the cystic form that is generally shed in feces. The most common ways to become infected with this parasite are through drinking contaminated water, eating unclean food or ingesting cysts from the contaminated ground.

Although this parasite may be tiny and simple, it has the potential to cause serious negative effects in susceptible people and animals. Young animals and those that are immunocompromised appear to be most likely to become ill from exposure. Damage caused when this parasite attaches to the intestinal wall can lead to diarrhea of varying severity. Foul-smelling, fatty stools that may be watery and contain blood or mucus is common. If left untreated, chronic intermittent diarrhea may result. In contrast, some animals may not show any symptoms at all.

Diagnosis of a Giardia infection is sometimes made by microscopic evaluation of the stool for the presence of trophozoites or cysts using a special flotation solution. This method is not always able to confirm an infection, as this parasite is often shed intermittently and can be difficult to diagnose. In some cases, stool samples are checked for antigens specific to Giardia to help rule in or rule out this parasite.

Treatment of Giardia generally involves using one or more oral medications. Metronidazole and Fenbendazole are two medications commonly used, either singly or in combination. Feeding a diet that is highly digestible may also be helpful in treating diarrhea or loose stools associated with this infection. Keeping your dog’s environment clean, dry and picking up stools immediately after they are passed will help prevent the spread of this parasite or re-infection of your pet. Bathing is also recommended during treatment to remove any cysts that could be on your pet’s fur. Practicing good hygiene, in general, is important to protect yourself and others from accidental infection.

If you have any questions, please give us a call at 204.253.2668.

Written by: Brenda K, RVT



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Last updated: August 3, 2021

Dear Clients,

In order to maintain everyone's safety and prevent the spread of COVID-19, the following procedures have been implemented:

If you have a fever, new or worsening cough, shortness of breath, runny nose, nasal congestion, loss of sense of smell, sore throat, painful swallowing, headache, muscle aches, fatigue, loss of appetite, chills, or fever we ask that you do not attend your pet's appointment.

If you have been instructed to self isolate for 14 days due to travel from Eastern Canada, travelled outside of Canada, had contact with someone known to have COVID-19 in the last 14 days, or are waiting for COVID-19 test results we ask that you do not attend your pet's appointment.


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Monday, Tuesday, Thursday: 7:30 am - 6:00 pm
Wednesday: 7:30 am - 8:00 pm
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Sunday: Closed


Have you welcomed a new furry family member to your home? We’d love to meet them! Visit our Must Know New Pet Owner Information page for useful resources and helpful recommendations for new pet owners.

Thank you for your patience and understanding and we look forward to seeing you and your furry family members again!

- Your dedicated team at St. Vital Veterinary Hospital