Why Is My Senior Dog Sleeping So Much?

My neighbor's Lab, Finn, turned ten last spring. He used to stand at the back door at six sharp waiting to be let out. Now she gets up and he barely moves. Lifts his head. Drops it back. She called me about it, genuinely worried. Most of the time the answer is nothing. Sometimes it isn't. The trick is knowing which.

Adult dogs sleep 12 to 14 hours a day. Seniors — dogs seven and up, roughly, though breed and size shift the line — usually run 16 to 20. Part of that is pure biology. Old dogs spend less time in real deep sleep, so total hours stretch to compensate. Everything they do costs more energy than it used to, and recovery takes longer. A long nap after a walk is not a medical event.

But real problems hide inside the same pattern.

Hypothyroidism is one. An underactive thyroid, very common in middle-aged dogs. It makes them slow, cold-seeking, often heavier without eating more. A blood panel catches it in minutes. Treatment is a cheap pill twice a day.

Then the big one: canine cognitive dysfunction. The dog version of early Alzheimer's. A disrupted sleep-wake cycle is one of its first signs, and the numbers in the literature are worse than most owners think. A 2022 analysis of 15,019 dogs from the Dog Aging Project found the odds of cognitive dysfunction rose 52% with every additional year of age. Older work from Neilson et al. (JAVMA, 2001) found 28% of dogs aged 11 to 12, and 68% of dogs aged 15 to 16, already showed at least one cognitive sign. Almost none of those dogs were diagnosed. A 2010 study in The Veterinary Journal pegged real prevalence at 14.2% across older dogs. The vet diagnosis rate was 1.9%. The gap is the whole story.

Arthritis is the one most owners miss. Radiographic studies put osteoarthritis prevalence above 80% in dogs over eight. A dog in pain sleeps more because moving hurts, not because it's tired. Watch the transitions. Getting up off the floor. That half-second pause at the top of the stairs. Or the way they lie down, weighted toward the good hip.

Heart disease, diabetes, anemia, and some cancers can look like sleepiness first and a diagnosis months later. Most senior dogs who sleep more are just getting old. Some aren't.

The question I'd actually ask is: what else changed?

Extra sleep on its own, with nothing else off, is usually just age. Extra sleep stacked with new water drinking, a change in gait, house accidents, pacing at night, or weight moving in either direction is a different conversation. The sleep-wake thing especially. Dogs with cognitive dysfunction often sleep hard during the day and then get restless or disoriented after dark. If your dog is up at three in the morning staring at a wall, call the vet. Not panic. A call.

A standard senior wellness panel (CBC, chemistry, T4, urinalysis) catches hypothyroidism, kidney disease, diabetes, and anemia in one visit. The AAHA Senior Care Guidelines say annually for dogs seven and up, twice a year past eleven. Most owners do them less often. I'd do them more.

Extra sleep in a senior dog is usually just aging. Extra sleep plus pacing, confusion, limping, or drinking more water is a vet visit, not a wait-and-see.

If your dog is seven or older and hasn't had a full senior blood panel in the last twelve months, book one. Ask for CBC, chemistry, T4, and urinalysis specifically. Most clinics charge $150 to $250 for the full workup. It rules out the four most common reasons an old dog slows down. And it costs less than the cognitive supplements people buy instead of doing it.

Good Years is a weekly newsletter for owners of dogs seven and up. Science-backed, marketing-skeptical, written by a guy who reads the studies so you don't have to.