What can cause bad breath?
Bad breath, or halitosis, is very common in dogs and cats; however, there are a wide range of possible causes. Some are simple to treat; others less so – but bad breath is almost always symptoms of an underlying problem.
There is one, harmless cause of halitosis – eating something rotten or smelly (much more common in dogs than cats)! Some dogs love eating faeces or rotting food; this may be habit, or greed – but in a small percentage of cases is due to a condition called pica. This is when the animal will eat pretty much anything, whether or not it is actually food-like, and may be due to mineral or vitamin deficiencies or certain brain diseases. In most cases, however, eating rotting or smelly things isn’t due to a disease condition (although it may well lead to a nasty episode of vomiting and diarrhoea!).
Metabolic diseases can also cause bad breath – especially diabetes and kidney failure. These conditions are both associated with changes in urination and drinking, and often weight loss. If untreated, both are potentially fatal. In diabetes, the breath may smell sweet (because of the excess sugar in the bloodstream); sour (because of increased bacterial growth, as the bacteria feed on the sugar); or musty (as yeasts grow in the mouth). In kidney failure, the breath may smell metallic (due to a build-up of toxins and waste products that the kidneys aren’t filtering).
Diseases of the respiratory tract such as sinusitis, nasal infections, and nasal tumours may also lead to bad breath…