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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.

Diagnosing and treating disease in old animals can be much more complex than treating disease in young animals

With advancing age a series of age-related changes occur in many tissues which effectively reduces the amount of functional tissue with the organ. These changes are usually slowly progressive and irreversible.

At the same time as ageing changes are occurring there is an increasing chance that an age-related disease will develop. Some of the common diseases seen in old cats and dogs are listed in the following table : 

Dogs Cats
Heart valve disease (endocardiosis) Obesity
Obesity Hyperthyroidism
Hypothyroidism Diabetes mellitus
Diabetes mellitus Kidney failure
Kidney failure Dental disease
Cushings Disease (hyperadrenocorticism) Cancer
Dental disease  
Liver disease  

One of the problems for veterinarians is that some of these diseases can be subclinical - that is present in the animal but not causing any signs. So it is not uncommon for an old animal to have disease in more than one organ at the same time which can make treatment more complex. 

Also, disease in a major organ (eg heart, liver, kidney) can cause secondary problems in other organs. For example, kidney failure is often associated with an increase in blood pressure, which in turn can cause damage to the eyes resulting in blindness.

Giving drugs or a general anesthetic to an old animal may cause problems if subclinical disease is present. For example, some types of anti-inflammatory drug or a general anesthetic can cause acute kidney failure in old animals which already have sub-clinical kidney disease.

Provet recommendation for owners with old animals :

  • If your pet shows any unusual signs get a veterinary opinion as soon as possible so that an early diagnosis can be made and treatment can be started as soon as possible


Updated October 2013