Giardia in dogs or cats: symptoms, treatment and the best aftercare
Giardia is one of the most common intestinal parasites in dogs and cats – and symptoms sometimes persist even after treatment. Why does this happen, and what is the best approach for full recovery?
Giardia is a single-celled intestinal parasite found in dogs, cats, and humans. It attaches to the small intestine lining, affecting nutrient absorption and digestion, often causing diarrhea.
It is especially common in environments with many animals, such as kennels, boarding facilities, or multi-pet households.

Infection occurs through contact with infected feces. The parasite is ingested via contaminated water, soil, or direct contact. Giardia forms cysts in the intestine that are shed in feces and can survive for months in the environment.
Because shedding is irregular, a single fecal test may not be enough. Giardia One-step rapid tests are more reliable, and multiple tests are recommended.
Common treatments include Fenbendazole (Panacur), Metronidazole (Flagyl), or a combination. Always complete the full course.
Even after successful treatment, diarrhea may continue due to disruption of the gut microbiome (dysbiosis), caused by both infection and medication.
Probiotics can help restore balance in the gut microbiome after Giardia infection.
Giardia cysts are highly resistant:
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