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Sachem Animal Hospital

Helping Your Elderly Dog with Senility

Old dog laying in bed

As veterinary medicine has become more sophisticated, nurturing your pet has become the rule rather than the exception and the population of elderly pets has grown steadily.

As an animal advances into their twilight years, changes take place in all organ systems including the brain. Dogs, dependent upon breed, are considered senior citizens when they reach 7 to 10 years of age.

Cognitive Dysfunction Syndrome (CDS) / Canine Cognitive Disorder (CCD)

CDS/CCD is commonly referred to as senility or "old dog" syndrome. A gradual, progressive loss of thinking (cognition) processes such as awareness, perception of surroundings, ability to learn and memory are the major components of the disorder.

CDS can lead to a break in the close bond shared between pet and family members as changes in temperament or house-training can occur. Many people think that it is normal for their elderly dog to gradually lose its energy and interest in life, and choose to tolerate cognitive aging far longer than is necessary. They either avoid veterinary advice altogether or wait until bladder or bowel control is gone before seeking an opinion.

Signs of CDS are fairly straightforward, but it also requires observation on your part.

As a responsible caregiver, noting changes in the behavior of your elderly dog should not be difficult if there is already an established bond. Blood tests, urine analysis, X-rays, and other tests may be necessary to diagnose CDS once symptoms appear, as many times other illnesses may make diagnosis challenging due to an overlap in symptoms.

Not all dogs show these signs. However, one thing is certain: the signs are progressive and will completely incapacitate your dog in time.


  • Weight loss / Appetite changes

  • Confusion, disorientation, anxious look, staring into space, getting lost in the house

  • Difficulty navigating the environment (e.g. stairs)

  • Altered pattern of sleeping and waking

  • Loss of learned behaviors such as obedience commands and house training

  • Reduced responsiveness or a change in relationship with family such as aloofness, aggression, apparent loss of recognition of familiar people or sounds

  • Increased thirst

  • Excessive panting

  • Abnormal vocalization such as howling or monotonous barking


Prior to the advent of deprenyl, a prescription-only drug that helps minimize symptoms by enhancing brain dopamine levels, there was no treatment available. Dopamine is an integral part of brain function because it increases cognitive awareness. If depleted, it results in lower cognitive ability.

While deprenyl is not a cure, it can symptomatically reverse the signs of aging by increasing dopamine in the brain and turning back the aging clock. The goal of treatment is to provide a better quality of life for your dog and slow the progression of symptoms.

Like any drug treatment, however, not all dogs respond to deprenyl. Statistics show that one-third of canine patients respond extremely well, one-third respond reasonably well and one-third do not respond at all. Unfortunately, there is no way to tell prior to drug therapy if your dog will respond to treatment.

CDS is a very real disorder that can affect any dog of any breed.

As your dog ages, be aware of changes both physically and mentally. Adjust his lifestyle to better suit his decreased abilities.

By consulting with your veterinarian and providing your elderly dog with comfort and compassion, you are making his quality of life the top priority. That is the best treatment any pet can receive.