What causes bad breath?

Did you know that bad breath is the number one reason for a veterinary oral exam? It is often the first sign that there is a more serious oral health problem. This bad breath, also called halitosis, is common when little dental care is provided to the animal. It can also result from other conditions such as chronic liver disease, gastrointestinal disease or oral tumors. Bad breath can also be caused by an oral infection induced by a foreign object such as a piece of wood. However, in the vast majority of cases, halitosis is present when periodontal disease has been present for some time as well.

How does it appear?

In general, bad breath results from bacterial metabolism resulting from the breakdown of protein substrates from the oral cavity and food. The odor, produced by bacteria, is derived from volatile sulfur compounds such as hydrogen sulfide and methyl mercaptan. In short, bad breath comes from bad bacteria. We can call them that because they have several negative consequences on the body. For example, the compounds they produce increase the level of inflammation in the gums and they can even prevent wounds from healing! These bacteria are largely found in what is called dental plaque. They are also present on the back of the tongue and in the periodontal pockets. The latter represent the space that is created between the tooth and the gum during periodontal disease.

What can I do about the bad breath of my pet?

To reduce bad breath, practicing good oral hygiene with your pet is necessary. This practice will remove accumulated plaque while eliminating some of the bad bacteria. The best method is to brush the teeth with an adapted toothbrush. Indeed, brushing teeth provides a mechanical movement that helps dislodge bad bacteria, including those producing bad odors. For greater effectiveness, you can add a product such as toothpaste or dental gel. When selecting a product, it is important to verify that it attacks the bacteria directly, since they are the source of the problem. There are some products that can be classified as odor neutralizers. These products do not attack the bacteria, they simply change the smell by temporarily camouflaging the real problem, which is the bacteria. It’s like always using gum instead of brushing your teeth. Even though the bad odor is camouflaged, the bacteria continue to accumulate and can lead to more serious problems than just the presence of bad odor. The bacteria are still present in our mouths and the odor neutralization is only temporary. In summary, tooth brushing attacks bacteria mechanically and it is possible to combine brushing with an effective product to have an additional effect against bacteria.

Did you know that among all the bacteria in the oral cavity, some are directly associated with bad breath? The more these bacteria are present, the worse the bad breath will be! Some of these bacteria are also found in humans!

Finally, if you are on a good dental care routine with your pet and the bad breath persists, there may be an underlying problem. We recommend that you consult your veterinarian at this time. For more articles on dental health for your four-legged friends, we invite you to visit our blog!


Niemiec, B.A., Small Animal Dental, Oral and Maxillofacial Disease: A colour Handbook. 2011, London: Mansons.
Fiorellini, J.P., D.M. Kim, and S.O. Ishikawa, Carranza’s Clinical Periodontology. 2006, St-Louis: Saunders.
Lee, C.H., et al., The relationship between volatile sulfur compounds and major halitosis-inducing factors. J Periodontol, 2003. 74(1): p. 32-7.
Culham, N. and J.M. Rawlings, Oral malodor and its relevance to periodontal disease in the dog. J Vet Dent, 1998. 15(4): p. 165-8. vanSteenberghe, D. and M. Rosenberg, Bad Breath, a Multidisciplinary Approach 1996, Leuven, Belgium: Leuven Universiy Press.

Would you like to be notified when our next article is released? Subscribe to our newsletter!
Don’t miss our promotional offers, news and more!


Déjà connecté ? Accéder à votre compte