Stinky Dog Breath: Why Does My Dog’s Breath Smell Like Poop?

May 10, 2021
Photo: A King Charles Spaniel smiles as he has good oral health.

You love your dog but GOOD GRIEF! His breath reeks and makes you wonder whose butt he's been licking. (Spoiler: It's his butt he's been licking, duh!) Bad dog breath doesn't have to be a given, though. If your dog's breath smells like poop, there's an underlying cause for that. Yes, it may be because he's eating excrements (that's a whole different story) but most likely? He's not breaking his food down well enough and you're dealing with some residual effects! If you're wondering why your pet's breath smells like poop, read on!

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What Is Bad Breath in Dogs?

Let’s be real. Best friends as they may be, most dogs do gross things. They enjoy eating cat poop as if it’s a dessert, they have no issues going through days and days of trash for that leftover pizza crust, and well, they lick their butts. How on earth is their breath supposed to smell? Dogsț’ bad breath, or canine halitosis, is a common complaint of dog owners and is, at its core, exactly what it says: when your pup’s breath smells really bad.

Why Does My Dog’s Breath Smell Like Poop?

Okay, let us repeat ourselves and remind you that your dog does lick his butt. You know that, right? And butt-licking does lead to breath smelling like…butt. More particularly, poo, if we’re getting to the down and dirty of it.

But the thing is–like all of us–our breath isn’t really based on so much of what we put into our mouths as much as it is how our mouths and our guts combat that. If your fluffy friend’s breath smells like excrement or your dog has fishy breath, it’s likely that his microbiome isn’t healthy, and his dental hygiene is suffering.

Canine halitosis may also be caused by some sugar imbalances or kidney/liver disease your dog is dealing with, but most of the time, if your dog’s mouth smells, it’s because they’re not digesting their food properly, and they don’t have good dog gut health.

How Can I Help My Dog’s Breath Smell Better?

If your four-legged friend is suffering from poor oral hygiene, he’s going to have bad breath. Pieces of food left behind will entice nasty-smelling bacteria to hit your dog’s gums and teeth up for a good time, and the end result? Whew! Stinky dog breath!  It is important to have your dog’s teeth checked regularly, as tartar buildup can cause tooth decay or mouth infection, to prevent foul breath and improve the overall dental health of your pet. You can get your dog’s teeth brushed and cleaned professionally, or also do it yourself by using a dog toothpaste. Dental chews and treats can also help with maintaining your dog’s dental care.

If your dog’s gut isn’t healthy, stinky dog breath can become more than a smelly annoyance; it may even be a sign of an underlying health condition. When the digestive system struggles to process toxins and waste, odor-producing bacteria can build up in the gut and mouth. In some cases, seriously bad breath may indicate kidney or liver disease, since a dog’s kidneys and a dog’s liver help filter and process toxins throughout your pup’s body. These issues can progress to organ disease or even organ failure, so supporting digestion plays a crucial role in a dog’s health and in preventing internal organ failure.

You might wonder how the gut affects the mouth at all, especially if your dog has recently eaten poop or has breath that smells like feces. The truth is that what happens in the gut doesn’t stay in the gut. When bad bacteria overgrow, they release foul-smelling compounds that travel upward and affect breath in your dog. That’s why fresh breath requires more than oral health products or just brushing your dog’s mouth. You need to support the middle, the microbiome.

A thriving microbiome helps protect against oral infections, gum disease, and other emerging oral health issues, and it even helps promote good oral health from the inside out. Bernie’s Perfect Poop is made with dog food designed to support digestion and contains prebiotics, probiotics, fiber, and digestive enzymes that help break down nutrients properly. When dog foods formulated for gut health can break down foods more effectively, less food debris remains in the mouth, and the gut bacteria remain balanced.

Better digestion means your dog absorbs nutrients successfully, can filter and process toxins more effectively, and avoids many of the causes of bad breath linked to the gut. This internal support complements routine oral hygiene care, brushing, dental chews, and even annual professional dental cleanings. And while these suggestions don’t constitute medical advice or replace accurate diagnosis, they work alongside other oral health solutions your vet may recommend. Always ask your veterinarian for medical advice regarding pets, especially if you suspect an underlying health issue or very serious health issues. If the smell worsens or infections are present, your vet may suggest prescription medications, specialized diets, therapies, or further guidance so your furry best friend stays healthy inside and out.

Stinky Dog Breath: What Goes in Affects What Comes Out!

The truth is that a normal doggy smell is perfectly normal, but when pup’s bad breath smells like trash or breath smells like feces, it’s often a sign that something deeper is going on. Not all odors come from the mouth alone. Sometimes an imbalance in the gut or food that isn’t digested well leads to bad breath in dogs, even when you brush regularly. Good pet’s oral health habits will help remove waste materials stuck between the teeth, but the goal isn’t only to clean, it’s also to promote oral health and stop bacteria from building up in the first place. If your dog has bad breath that lingers after cleaning, it’s time to look beyond brushing and explore how gut balance helps treat bad breath more effectively than brushing alone.

While many odors are harmless, persistent bad breath can also point to a health issue underlying the smell. Kidney disease, liver problems, or even kidney issues can affect the body’s ability to handles toxins and waste, making a pup’s bad breath smell unusually sour or metallic. In severe cases, toxins build up in the body instead of being filtered correctly, putting your dog at risk of organ failure if it’s not successfully treated. That’s why breath that doesn’t improve with cleaning or a dog food designed for better digestion may indicate a need for a precise cause from a veterinarian. Your vet may recommend other oral health solutions, a change in prescription medications specialized diets, or supportive care to treat kidney or liver complications. None of this is meant to constitute medical advice regarding pets, but a reminder that when breath smell so bad that regular brushing isn’t enough or your dog can’t tolerate brushing, your pet may need immediate veterinary attention based on your pet’s condition.

FAQ

What causes a dog’s bad breath?

The most common cause of bad breath is a buildup of bacteria from leftover food on teeth, but it can also come from poor digestion, inflammation in the mouth, or even recently eaten poop. In some cases, dog breath smells like poop because food debris and gut imbalance create odors that travel back up through the mouth.

What are the most common breath in dogs causes?

Frequent breath in dogs causes include plaque on teeth, oral bacteria, and dietary imbalance. Some small dogs bad breath smells may also indicate a sign of an underlying condition, such as infection or a disease affecting the digestive or filtering organs.

Why does my dog’s stinky breath return even after brushing?

If dog’s bad breath smells return quickly after cleaning, brushing isn’t reaching the root issue. Even clean teeth can smell when food isn’t digested well. Gut imbalance and dietary irritation make breath smells like feces possible even when your pet appears healthy.

Should I worry if my dog’s breath smell so bad out of nowhere?

Yes. A sudden change where bad breath in dogs worsens may indicate infection, mouth injury, or kidney disease. Because odors can point to different causes, a veterinarian can provide an accurate diagnosis and identify the precise cause behind the change.

Can health issues make a dog’s bad breath worse?

Absolutely. Kidney issues and kidney disease can alter the way the body filters toxins, giving bad breath in dogs. These medical concerns require evaluation because they can be a sign of an underlying systemic condition.

Can poor digestion cause dog’s stinky breath?

Yes. When digestion is weak, food isn’t broken down properly, and trapped bacteria release odors that travel back up as breath in your dog. Even when dog has stinky breath but the teeth look clean, gut imbalance can create smelly gases that mimic dental problems. Sometimes this odor is perfectly normal after eating, but if it persists, it can point to oral health issues or a deeper underlying health condition.

A vet may recommend medications specialized diets therapies if the problem is linked to a disease affecting the digestive or filtering organs. Addressing the gut and supporting pet’s oral health together helps keep your pup healthier and happier.

Does brushing alone fix a dog’s bad breath?

Not always. Tooth brushing is important, but it doesn’t solve breath caused by gut imbalance, toxins, or internal diseases. Improving routine oral hygiene care and using recommended oral health products helps reduce poor oral hygiene bacteria on the teeth, but those steps can’t replace internal care. If the odor is strong or persistent, your vet may need to evaluate pet’s condition and rule out illness. Some cases can be successfully treated with diet adjustments, dental care, or health solutions, but prevention, including preventing internal organ failure when disease is involved, is key to keeping your dog’s breath healthy long-term.

Can human medications cause bad breath in dogs?

Yes. Giving human medications to pets without veterinary guidance can change how a dog’s body handles toxins, which can become a hidden cause of bad breath. Some medications affect dog’s liver or dog’s kidneys, and when those organs struggle to filter waste properly, a dog has bad breath that smells stronger and more sour.

How can I tell if my dog’s bad breath is from an internal disease?

If brushing and dental care don’t improve odor, the smell may be linked to gum disease, liver disease, or other oral health issues that point to an underlying health issue. Dogs with kidney or liver disease often develop breath that smells metallic or ammonia-like because waste can no longer be filtered efficiently. This odor change can be a sign of an underlying systemic problem that needs veterinary evaluation.

Important Dog Health Tip: Major changes to diet, supplements, or activity levels should take your dog’s individual health history into account. When in doubt, seek professional input before adjusting your dog’s routine.

About the Author

The Bernie's Best Staff is a passionate team of pet lovers, dedicated to improving the lives of dogs through natural and science-backed nutrition. With diverse backgrounds in pet health, product development, and education, the team works together to bring pet parents valuable insights and helpful tips. Whether researching the latest in canine wellness or crafting educational resources, the Bernie's Best Staff is committed to helping dogs thrive. When they’re not hard at work, you’ll find them spoiling their own furry family members and embracing every moment of joyful chaos that comes with life as a dog parent.

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