Impact of Antibiotics on the Dog Microbiome: What Every Dog Parent Should Know

For veterinarians, antibiotics are a crucial tool for treating bacterial infections in animals. However, these antibiotics aren’t selective when eliminating bacteria in your dog’s gut microbiome. As the drugs wipe out “bad” bacterial pathogens, your dog’s gut could also lose “good” bacteria that help the digestive system function properly.


Some of those beneficial bacteria:

  • absorb crucial nutrients
  • aid in fighting inflammation
  • help maintain a strong immune system

Loss of key beneficial bacteria may cause an ongoing bacterial imbalance in your dog’s gut that can contribute to or worsen health conditions like chronic digestive disorders.


A new study published in the Journal of Veterinary Internal Medicine investigated the effects of metronidazole on the microbiome in healthy dogs. The authors found that a 14 day course of treatment with metronidazole given to healthy dogs, resulted in significant changes in microbiome composition, including severely decreased amounts of a key group of beneficial bacteria, Fusobacteria.

After 30 days of post-metronidazole treatment, the dog's bacterial community did not recover, the canines were missing important bacteria associated with healthy gut function.

In this video, Dr. Karen Becker and Rodney Habib discuss the impact of metronidazole and what you can do to support your dog after a course of this medication.

Watch the video to get a coupon code for 25% off all AnimalBiome products.

Key Takeaways

If your dog has taken metronidazole or broad spectrum antibiotics, AnimalBiome’s Gut Health Test can assess the state of your dog’s gut microbiome.

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