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This information is provided by Provet for educational purposes only.

You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Foul smelling breath - can be a sign of serious disease, so take your pet to your veterinarian for a health check

Halitosis means an abnormal smell on the breath and there is almost nothing worse than a pet with foul smelling breath. As soon as you walk into a room the smell hits you, and it can be impossible to stay within 3 feet of the offender - particularly if he/she is facing towards you and panting !

It usually isn't too difficult to identify where the smell is coming from, although there are other locations which need to be eliminated as the source of the pong :

  • Ear infections can be quite strong and can permeate through the coat. 
  • A discharging abscess or a skin ulcer - located anywhere on the body 
  • In dogs discharged anal sacs ("scent glands") give off a very strong odour which can permeate throughout the body coat
  • A dirty, soiled coat

Once you are satisfied that the smell is definitely coming from the mouth - what could it be ? Well there are many possible causes :

  1. By far the most common cause of halitosis is dental disease - a build up of tartar (calculus) and bacteria, sometimes with decaying food particles (particularly in a food trap between teeth), gingivitis, gum disease and periodontal disease. (These have been covered in a previous Provet Petfacts Sheet - CLICK HERE  to go to it). Dental disease is particularly common in older animals. 
  2. The smell of freshly eaten pet food can linger on the breath for quite some time !
  3. A "foreign body" in the mouth - dogs and cats often get bits of bone or other objects stuck on or between their teeth, or sometimes bones (especially ribs) get stuck across the roof of their mouth - wedged between the upper arcade of teeth, up against the hard palate
  4. Kidney failure - due to urea on the breath
  5. Ulcers in the mouth - these can be present as a result of  kidney failure
  6. Cancers in the mouth or upper alimentary tract
  7. A sweet or fruity smell is often associated with diabetes (due to ketones on the breath)

Unfortunately, the foul smell of dental disease can be difficult to differentiate from the smell of urea caused by kidney failure, or an ulcerated cancer - so further investigations or tests are needed. Indeed, an old animal could have more than one problem at the same time ! For this reason you should take your pet to your veterinary surgeon if it has bad breath so that an accurate diagnosis can be made.


Updated October 2013