Is My Pet Acting This Way Due to Old Age or Is He Sick?

Older dog lying down on the floor
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Question: Is My Pet Acting This Way Due to Old Age or Is He Sick?

Changes happen as pets age, similar to the changes seen as people age. Sight and hearing may be diminished, pets may sleep more, and so on. These are expected changes. However, people often miss potentially serious signs of illness in their pets by writing off symptoms as "just old age" when a veterinary exam is in order. This FAQ outlines what to watch for as your pet enters the senior years.

Answer: One of the most common questions for veterinarians is something along the lines of "is my pet just ____ (fill in the blank) due to old age?" The symptoms range from sleeping all of the time to drinking more water. Weight loss (or gain) is also easily excused away as "old age". Yes, some changes are inevitable as we age, but there are many changes that are not considered "normal" at any age and should be checked out by your veterinarian to rule out underlying disease.

Some people may argue that if the pet is already old, an extended treatment regime would not add much quality to the pet's life in the case of advanced age. This may be true -- something to discuss with your veterinarian. It is important to note, however, that a pet may simply seem older due to illness and, once restored to health, exhibits increased energy and zest. This is when the phrase "acting like a puppy (or kitten) again" comes to mind.

A dog is considered to be a "senior" after age 7 (varies with the breed - giant breeds are considered senior at 5 or 6) and a cat is considered to be a "senior" after age 10 or so. An annual veterinary examination is essential for keeping your pet in optimal health and staying on top of age-related changes.

What is to be expected as pet ages? This is not a definitive list, but here are some common age-related changes to watch for:

  • less active overall
  • sleeps more (especially cats)
  • reduced sense of hearing
  • reduced sense of sight
  • less able to handle temperature extremes
  • reduced muscle mass


Common Symptoms

Below is a list of common findings that are often explained away as changes related to "old age". These changes may be symptoms of a disease process. If you notice any of these symptoms, a call to your veterinarian is warranted:

  • weight loss or gain
  • loss of appetite
  • foul breath/dental disease
  • lethargy
  • drinking and/or urinating more than usual


More About Senior Pets: ​All About Senior Dogs and Cats - Main Index

This list is focused on age-related changes, it is not a comprehensive health checklist. Any time that you notice a change in your pet (at ANY age) that you are unsure of, please call your veterinarian to discuss.