Overview
It is normal for older dogs to sleep more than they did when they were younger. In the day, they usually have one or two hours of activity and then nap. But if a dog has radical changes in his sleeping patterns or sleeps through events he normally would be alert for, then that's a sign to take your dog to the vet.
Incontinence in Females
It is normal for senior dogs to have incontinence problems. But there may be a problem in older spayed females that can be easily fixed. If your dog is usually great at house training but suddenly urinates while she sleeps, she may have this problem. If the senior dog does not have any other alarming conditions like loosing appetite or losing coordination, chances are that she only needs some medication in order to tighten up the bladder muscles. Please see a vet as soon as possible.
Narcolepsy
This is a genetic disorder seen most in Dobermans, dachshunds and Labrador retrievers. It can develop at any time in a dog's life, not just in the senior years. This is when the dog suddenly falls asleep without warning for up to half an hour at a time and then seems perfectly normal. Sometimes very exciting events can cause the dog to suddenly fall asleep. The dog also may seem very sleepy all day. Narcolepsy is a treatable condition.
Canine Dysfunction Syndrome
Dogs can go through a "doggy Alzheimer's" in old age. Just one of the many symptoms is sleeping too much and sleeping at unusual times. For example, if the dog normally sleeps through the night, the dog will suddenly sleep all day and be awake and pacing all night. Dogs with CDS also get stuck in corners, do not recognize familiar people or objects, have accidents in the house and bark for no reason at all.
Liver Disease
Liver disease in older dogs can also produce most of the same symptoms as for canine dysfunction syndrome, including sleeping too much or sudden changes in sleeping behaviors. The dog needs to go to the vet as soon as possible.
Impending Death
Some senior dogs seem to instinctively sense when it is their time to die, whether they are suffering from a serious illness or not. For a couple of days, weeks or months, they will sleep a lot more than usual and not be as curious about much of anything. But if they do not seem to be in any pain, seem to have their mental facilities about them and still enjoy their food, then there is not much you can do except keep them comfortable.
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