Metronidazole for Dogs: When Vets Prescribe It
Veterinary references checked with PetHealth+ · Last reviewed June 2026
By Kaiser Khan , Founder Veterinary references checked with PetHealth+ ( process ) Last reviewed Cite this page How we research & review
Metronidazole treats certain GI infections and giardia. Complete the full course and report neurological signs like wobbliness — overdose can cause toxicity.
Uses
Diarrhoea from giardia, colitis, and anaerobic infections.
Side effects
Nausea, drooling, and rare neurotoxicity at high doses.
Avoid alcohol-based compounds
In other medications concurrently unless advised.
Related: Dog diarrhoea · Dog vomiting
Frequently asked questions
Can metronidazole cause dark stool?
It can darken urine — mention unexpected changes to your vet.
Should it be given with food?
Food reduces nausea for many dogs.
How long is a typical course?
Often 5–10 days — finish all tablets even if diarrhoea improves.
Is metronidazole safe for puppies?
Used when indicated — dose by weight under vet supervision.