Why Does My Dog Have Bad Breath?

Call your vet now if

• Your dog's breath has changed suddenly or become much stronger over a few days
• The breath smells sweet, fruity, like ammonia or otherwise unusual
• There is swelling of the face, jaw or under the eye
• Your dog is drooling more than usual, especially if the saliva is tinged with blood
• They are dropping food, chewing on one side, pawing at their mouth or refusing to eat
• You can see a broken tooth, a lump in the mouth or bleeding gums
• Bad breath comes alongside vomiting, drinking much more than usual, tiredness or weight loss

Is a bit of "dog breath" normal?

Dogs are never going to smell of mint, and a faint, slightly meaty smell is common, particularly just after eating. What is not normal is a strong, lingering odour that you notice from across the room, or breath that makes you pull back when your dog comes in for a cuddle.

Many owners assume bad breath is simply part of having a dog. In reality, it is often one of the earliest signs that something in the mouth needs attention. The good news is that it is also one of the easiest signs to notice, which gives you a chance to act early.

The most common reason: dental disease

By far the most common cause of bad breath in dogs is dental disease. It tends to build up quietly over time:

• Plaque is a soft, sticky film of bacteria that forms on teeth every day.
• If it is not removed, it hardens into tartar, the yellow or brown crust you may see near the gum line, especially on the back teeth.
• Bacteria around the tartar irritate the gums, causing gingivitis, where the gums look red and may bleed.
• Over time this can progress to deeper gum disease, which can affect the tissues holding the teeth in place and become painful.

The bacteria involved produce smelly compounds, which is why breath often worsens as dental disease progresses. Smaller breeds and older dogs are often more prone to dental problems, though any dog can be affected.

Dogs are very good at hiding mouth pain. Many carry on eating even when their teeth are sore, so a lack of obvious discomfort does not mean all is well.

Other things that can cause bad breath

While the mouth is the usual source, breath can also be affected by:

• Something stuck between the teeth, such as a splinter of stick or bone
• A broken or damaged tooth
• Lumps or growths in the mouth
• Eating something unpleasant, such as rubbish or another animal's droppings
• Problems elsewhere in the body, which can sometimes change the smell of the breath

Because some of these possibilities are serious, it is worth having your vet check any persistent or unusual bad breath rather than assuming it is "just teeth".

How to check your dog's teeth and gums

A quick look at home can tell you a lot. Choose a calm moment when your dog is relaxed, and keep it short and positive.

1. Gently lift your dog's lip at the side of the mouth. You do not need to open their jaws to see most of the teeth.
2. Look at the teeth near the gum line. Clean teeth look white or cream. Yellow or brown build-up is likely to be tartar.
3. Look at the gums. Healthy gums are usually pink (some dogs have natural dark patches). Redness along the gum line, swelling or bleeding are signs to mention to your vet.
4. Check for anything unusual, such as a broken tooth, something stuck, a lump or a sore area.
5. Praise your dog and offer a reward afterwards so they learn that mouth checks are nothing to worry about.

If your dog seems uncomfortable, pulls away sharply or growls, stop. Pain can make even gentle dogs defensive, and that in itself is a reason to see your vet.

Brushing: the best everyday habit

Regular tooth brushing is the most effective thing you can do at home to slow plaque build-up. Daily brushing is ideal, but even a few times a week helps.

• Use a toothpaste made for pets. Human toothpaste is not suitable for dogs, as some ingredients can be harmful if swallowed. Pet toothpastes are designed to be swallowed safely and often come in flavours dogs enjoy.
• Use a soft brush. A dog toothbrush, a finger brush or a soft child's brush can all work.
• Start slowly. Begin by letting your dog lick a little toothpaste from your finger. Then gently rub a finger along their teeth, and only later introduce the brush.
• Focus on the outside surfaces. These are where most tartar builds up, and you do not need to brush the inner surfaces that the tongue helps keep cleaner.
• Keep sessions short and positive. A minute or two with lots of praise is plenty.

Brushing helps prevent new build-up, but it cannot remove tartar that has already hardened. If your dog already has tartar or sore gums, your vet may recommend a dental check and clean first, and brushing can then help keep the teeth healthier afterwards. Do not try to scrape tartar off yourself, as this can damage the teeth and gums.

There is more practical advice in our guide to dental care for dogs and cats.

What about chews and dental products?

There are many chews, toys, water additives and special diets marketed for dental health. Some may help a little alongside brushing, but none are a full replacement for it. Be cautious with very hard chews, bones and antlers, which can break teeth. If you are unsure which products are sensible for your dog, your vet or vet nurse can advise.

When to see your vet

It is a good idea to have your dog's mouth checked at their routine health checks, and to book an appointment sooner if:

• Bad breath persists even with regular brushing
• You see tartar, red gums or bleeding
• The smell has changed suddenly or seems unusual, such as sweet or like ammonia
• Your dog is drooling, dropping food, chewing oddly or has any facial swelling
• Your dog seems generally unwell as well as having bad breath

Your vet can examine the mouth properly, and some problems, particularly those below the gum line, can only be fully assessed under anaesthetic. They will talk you through what they find and what, if anything, needs to be done.

If you are unsure whether a sign needs attention, our guide to signs your pet needs a vet can help you decide.

The takeaway

Bad breath is your dog's way of telling you to look in their mouth. In most cases it points to dental disease, which is common, manageable and much easier to deal with when caught early. A regular peek at the teeth and gums, a brushing routine with pet toothpaste and routine vet checks will help keep your dog comfortable. Any sudden or unusual change deserves a prompt call to your vet.