Metronidazole for Dogs: Vet-Reviewed Dosage and FAQs 

If your dog has been suffering from diarrhea or other irritable bowel symptoms, your vet might prescribe metronidazole. It’s an antibiotic used to treat intestinal inflammation in both humans and animals. But how exactly does it work? Are there any safety concerns to be aware of? Keep reading to learn more about using metronidazole for dogs.

What Is Metronidazole?

Metronidazole is a powerful antibiotic, meaning it’s used primarily to treat infections caused by bacteria and parasites, such as giardia.³ Although it’s typically prescribed for people, it’s also commonly used to treat illness in dogs, cats, and even horses. That’s because many of the same organisms that infect humans can also infect animals.

How Does Metronidazole Help My Dog?

So what exactly can metronidazole do for your pooch? It’s mainly prescribed when a dog is suffering from inflammatory bowel disease (IBD). Despite the name, IBD actually isn’t a disease. It’s a syndrome — inflammation of the intestinal lining — that can be caused by diseases, infections, or dietary issues.⁴

The most prevalent symptom of IBD is chronic diarrhea. In cases where bacteria or parasites have caused IBD, metronidazole helps relieve symptoms by directly attacking the culprits. Infectious pathogens tend to thrive in low-oxygen environments, which are in turn created by cutting off blood flow to damaged tissue. Metronidazole targets these anaerobic organisms and prevents them from creating DNA, effectively destroying the pathogens.

How Safe Is Metronidazole for Dogs?

All that might sound pretty intense! The good news is that metronidazole is considered very safe for most dogs. There are a few caveats, which you should discuss with your veterinarian:

• Metronidazole is not safe for dogs who are pregnant or nursing, or for young puppies.
• Dogs with kidney disease, liver disease, low white blood cell counts, or seizures should not take metronidazole.
• Long-term use can have adverse effects, so discuss length of treatment with your vet.

Metronidazole for Dogs: Side Effects

As with any medication, there are side effects to be aware of. Allergic reactions are always a possibility. Be on the lookout for rashes, hives, or changes in breathing. Other common side effects include:

• Drooling
• Fatigue
• Loss of appetite
• Gagging
• Vomiting
• Diarrhea
• Fever
• Discolored urine

Even rarer, though not unheard of, are the neurotoxic side effects. Metronidazole can penetrate the blood-brain barrier to treat infections of the central nervous system. The trade-off is that it could negatively affect your dog’s nervous system as well. In extremely rare cases this can cause symptoms, including paralysis.

Speak to your vet if you’re concerned about any potential side effects. Their knowledge of your pooch’s medical history will help them give you an informed opinion on the best course of action.

What’s the Best Metronidazole Dosage for Dogs?

The right dosage of metronidazole for your dog depends on what’s being treated.⁵ When dealing with parasites, your vet may prescribe between 7 – 29.5 mg/lb every 24 hours. Bacterial infections might require between 11 – 22 mg/lb twice every 24 hours.

As always, follow your vet’s advice and update them regularly on your dog’s progress. It may take a while to find the most effective dose for your pup.

How Much Does Metronidazole Cost?

You can expect to pay between $13 and $28 for a treatment course of metronidazole for dogs.⁶ Still, unexpected veterinary bills — even small ones — can have a big impact on your bank account. With a dog insurance policy, you can get reimbursed for most prescriptions, as well as additional treatments your dog might require.² Don’t have pet insurance? Now is as good a time as any to find out how much you could save. Get a free quote from MetLife today!¹