The most likely cause of bad breath in an elderly dog is dental disease. If he will not let you examine his mouth, then I recommend you take him to your veterinary surgery and ask the vets or nurses there to take a look. If they do discover problems with his teeth or gums, they may recommend an anaesthetic to clean his teeth and take out any that are rotten, but they will only do this if they feel he is otherwise fit and well enough to withstand the anaesthetic. If this is an issue, they may offer an alternative treatment, such as antibiotics, which may not cure the underlying cause but will help to reduce the bacteria which are often the cause of bad breath.

Other possible causes of your dog’s bad breath include digestive upsets and anal gland disorders, however these are normally accompanied by other more obvious signs and are less likely if your dog seems otherwise fit and well.

It sounds unlikely that your dog will tolerate having his teeth cleaned, but once you know he is comfortable in his mouth you may wish to consider getting him to increase his dental exercise with some of the many dental chews or dental toys that are now widely available.

Answered by Miss Gemma Clark BVSc, PG(Dip), MRCVS.