Why does my dog’s breath smell so bad?

It’s a special kind of disappointment when you go in for a cuddle with your dog only to be met with a bad dog’s breath. You know… the breath that makes you cover your mouth, turn your head, and maybe even feel a bit nauseous.

The culprit most commonly associated with smelly dog or puppy breath is food, but you may be surprised to learn that halitosis (the medical term for bad dog’s breath) is often much more complicated than fish for dinner.

In this post, we’ll cover the differences—and a few similarities—between your mouth and your dog’s mouth, what the source of your dog’s bad breath may be, and what you can do from home to get rid of your dog’s bad breath (or prevent it in the first place).

We’ll start with a brief anatomy lesson.

A look inside your dog’s mouth

Have you ever taken a look inside your dog’s mouth (when you weren’t prying open their jaws to fish a dog-unfriendly food or toy out)? It’s a pretty fascinating place if you ask us.

Dogs’ mouths have many functions, but four top the list: grasping, chewing, swallowing, and communication (biting, licking, barking, and so on).

Inside your dog’s mouth, you’ll find soft tissue (cheeks, gums, and tongue) and hard structures including their upper and lower jaws and, of course, teeth. If you’re a parent to a puppy more than 8 weeks old, a quick tooth count should reveal 28 deciduous (baby) teeth. These teeth typically begin to fall out around 3 months to make way for the 42 permanent teeth that arrive sometime around 6-8 months.

Each tooth in your dog’s mouth consists of a crown (above the gum line), one to three roots (below the gum line), and four layers of tissue:

  • Pulp (the soft middle tissue responsible for transmitting hot, cold, and other sensations)
  • Dentin (a hard, yellowish tissue that encases the pulp)
  • Enamel (the white outer cover over the dentin of the crown)
  • Cementum (covers the outer surface of the roots)

EXPERT TIP: Does your dog drool when they’re excited? Don’t worry—this is normal! Salivation is a natural physiological reaction to stimuli, and although we see it most around food, a new toy or the promise of a walk can trigger the same response.

Last, but certainly not least, is saliva. This fluid is meant for more than just drool; it’s full of electrolytes, and antibacterial and antiviral proteins.

Saliva helps protect dogs’ teeth and oral mucosa (the wet soft tissue membrane that lines your dog’s mouth) by buffering and lubricating tissues and clearing away bacteria.

While you most definitely aren’t expected to memorize canine anatomy, a basic understanding of what’s inside your dog’s mouth will help you have productive conversations with vet professionals when you book your dog in for a routine oral hygiene check—something we recommend at least every 6 months.

EXPERT TIP: Many veterinary clinics offer courtesy oral health assessments with their registered veterinary nurses, so don’t be afraid to take them up on this offer.

Why does my dog’s breath bad all of a sudden?

If you’ve noticed a sudden and smelly change in your dog’s breath but aren’t sure why the likely culprit is dental disease.

Just like us dog parents, dogs’ teeth are covered with an invisible layer of bacteria called plaque. Plaque alone can be potent enough to alter your dog’s breath, but the situation can go from bad to worse when it makes contact with the gum and causes inflammation.

Untreated plaque becomes hard dental tartar (calculus) after about three days. Unfortunately, calculus can’t be “undone” with toothbrushing; because it consists of calcium salts that mineralize, it provides the perfect hiding spot for bacteria and can lead to tooth decay and smelly sulfur compounds.

When teeth begin to decay, holes or pockets start to appear below the gumline—another prime spot for food particles to settle in and emit smells as they slowly decompose. Worse yet, this process can result in an abscess (a collection of pus that develops as your dog’s body tries to fight off bad bacteria).

Bad dog’s breath certainly isn’t glamorous, but the more you know about the stages and symptoms of dental disease, the better able you are to identify and address it.

The 4 stages of dog tooth decay

Dog tooth decay typically plays out in four stages. As you might have guessed, the farther dental disease progresses, the more aggressive (and, to be blunt, expensive) the treatment:

Inflammation of the gums (gingivitis) only (no damage to the attaching tissue and bone).

  • Treatment: Regular home care and routine veterinary dental cleanings.

Gingivitis with 25% tissue detachment around the tooth. This is called early periodontal disease and is typically identified with dental x-rays.

  • Treatment: Veterinary dental cleanings with subgingival scaling (cleaning below the gumline) wherever there are pockets of tissue detachment; potential antimicrobials; and regular home care.

Moderate gingivitis with up to a 50% loss of attachment around the tooth. This is called moderate periodontal disease.

  • Treatment: Veterinary dental cleanings with subgingival scaling and root planing (deeper cleanings and/or advanced treatments), antimicrobials, and potential extractions.

Severe gingivitis with over 50% of attachment lost from around the tooth. This is called severe periodontal disease.

  • Treatment: Advanced surgery and treatments or, more often, extraction.

Although dental disease and tooth decay is usually the main reason behind bad dog’s breath, it’s not the only one.

Other causes of bad dog’s breath

EXPERT TIP: Did you know that diabetes can cause several different smells? Depending on the levels of excess blood glucose and what’s happening in conjunction, your dog’s breath may smell sweet, sour, or musty on a given day.

If your dog’s teeth are in tip-top shape, bad dog’s breath may be the result of other conditions such as:

  • Pica. Don’t be fooled by the cute name. Pica is a condition marked by craving and ingestion of non-food items such as metal, clothing, paper, or—you guessed it—poop.
  • Metabolic diseases like diabetes and kidney disease. The type of bad dog’s breath smell (metallic, for example) is the result of bacterial buildup.
  • Respiratory diseases such as sinus inflammation and nasal inflammations. Here, the smell originates from pus draining from the sinuses into the mouth.
  • Gastrointestinal disease. Whether your dog is dealing with a megaesophagus (a dilated esophagus) or a food-induced vomiting session, acid reflux can have smelly repercussions.
  • Skin diseases around or inside the mouth, are generally due to tissue destruction and infection.

How to fix your dog’s breath

The best thing you can do for your dog’s breath is to make a habit of booking regular dental cleaning appointments. Even if your dog’s teeth look healthy and they seem in good spirits, dog parents are often surprised by what’s brewing below the gumline.

Ahead of your dog’s routine dental cleaning, your veterinarian will perform a pre-surgical exam and may recommend blood work to ensure they are healthy to undergo the procedure. Dogs are placed under gas anesthesia for dental cleanings so they stay still and calm throughout (a bit like the laughing gas dentists will sometimes use for us humans).

If the thought of putting your dog under anesthetic makes you feel uneasy, it may help to know that typical clinic protocol involves a vet nurse staying by your dog’s side the entire time, carefully monitoring their vitals (things like heart rate and blood pressure) every 5 minutes.

Your veterinarian will likely advise you to be on standby during the dental procedure to share their findings and come up with a treatment plan everyone feels comfortable with. They will often call or text you once they have taken all the necessary dental x-rays and have thoroughly examined your dog’s teeth and mouth.

Your dog will be kept in-clinic until your veterinarian feels that they are fully awake, comfortable, and ready to safely head home. They will book a discharge appointment with you later in the day to answer any and all questions and to go over any instructions or medications.

EXPERT TIP: If you’re in a pinch and wandering around a pet store wondering which tube of toothpaste is right for your dog, look for the VOHC (Veterinary Oral Health Council) seal of acceptance. Your vet team will have plenty of recommendations, too.

Veterinary Oral Health Clinic Badge - Waggle Mail - Dog's Breath Blog

Home remedies for bad dog’s breath and dental care

We’ve said it before, and we’ll say it again: prevention is the best approach to optimal dog health and wellbeing. So what can you do from home for the dog’s breath? A lot, actually!
In many ways, consistent at-home care is similar to what we as humans do to take care of our mouths and teeth:

  • Daily toothbrushing
  • Dental diets and chews
  • Toothpaste and gels
  • Water additives and topicals

You may be surprised to learn the canine oral health market is pretty saturated; not all products meet our rigorous Waggle Mail quality pre-screen when we’re selecting products for our personalized dog subscription boxes.

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