Why Is My Dog Sleeping More Than Usual?
Dogs sleep a lot — adults average 12–14 hours, seniors and puppies even more. So when owners notice their dog sleeping more than usual, it can be genuinely difficult to know whether this is “they had a big day” or “something is wrong.” The difference is in the details.
Increased sleep in dogs is benign when it follows unusual exertion, occurs in hot weather, or is part of normal senior ageing. It becomes a concern when it’s accompanied by other changes — appetite loss, reluctance to interact, pain signals, increased thirst — or when it appears suddenly in a dog with no obvious benign explanation.
How much sleep is normal?
| Life stage | Normal daily sleep | Notes |
|---|---|---|
| Puppies | 16–20 hours | Essential for development; concerns arise if they can’t be woken normally |
| Adult dogs (1–6 years) | 12–14 hours | Breed dependent — working breeds sleep less; giant breeds more |
| Senior dogs (7+ years) | 14–18 hours | Naturally increasing with age |
| Brachycephalic breeds | Up to 20 hours | Breathing effort during activity increases rest requirement |
Benign causes of increased sleep
Post-exercise recovery
A dog who had an unusually active day — a long hike, a trip to the beach, an extended play session — will sleep more the following 24–48 hours. This is normal physiological recovery and requires nothing except allowing the rest.
Hot weather
Heat increases the metabolic cost of maintaining normal body temperature in dogs, who regulate heat less efficiently than humans. Dogs are more lethargic in hot weather by design — it preserves core temperature. As long as the dog is drinking normally and can be roused to normal alertness, hot-weather sleepiness is benign.
Normal ageing
Senior dogs sleep more. This is well-established and unsurprising. An 11-year-old dog who sleeps 16–18 hours is not necessarily unwell — they are old. The concern is not the sleep duration itself but whether the dog engages normally when awake: eating, showing interest in their environment, responding to their name.
Post-vaccination
Mild lethargy for 24–48 hours following vaccination is a normal immune response. If it extends beyond 48 hours or the dog shows more significant symptoms, call your vet.
When increased sleep becomes a concern
The key diagnostic question is not “how long is my dog sleeping” but “what happens when they’re awake?” A dog who sleeps 16 hours and then wakes alert, hungry, interested in play, and responding to their name is probably fine. A dog who sleeps 14 hours and then wakes seeming dull, uninterested, and reluctant to engage is showing a different pattern.
Red flags alongside increased sleep
- Appetite changes — refusal of food in a dog who previously ate well
- Decreased water intake (or conversely, dramatically increased water intake)
- Dull, unfocused eyes when awake
- Reluctance to interact with family members they normally seek out
- Pain signals — difficulty getting up, reluctance to move, changed posture
- Vomiting or diarrhoea alongside the increased sleep
- Weight loss
Medical causes of unusual lethargy
Hypothyroidism
An underactive thyroid gland is one of the most common causes of unexplained lethargy in middle-aged dogs. Other signs include weight gain despite no appetite increase, coat changes, cold intolerance. Diagnosed with a blood test and managed with daily medication.
Anaemia
Reduced red blood cell count means reduced oxygen delivery to tissues — producing profound tiredness. Pale gums are the key physical sign. Causes range from parasite burden to immune disease to chronic illness.
Infection
Any systemic infection — bacterial, viral, or parasitic — increases the body’s energy demands and produces lethargy. This is appropriate immune-response biology: rest conserves energy for fighting infection.
Organ disease
Kidney disease, liver disease, heart disease, and Addison’s disease all produce lethargy — often before other symptoms are obvious. Blood and urine panels catch most of these early.
Pain
Chronic pain exhausts dogs. A dog with undiagnosed arthritis, dental pain, or internal discomfort may sleep more as a pain-coping mechanism. See limping after sleeping as a related signal.
Canine cognitive dysfunction
In older dogs, sleep pattern reversal — sleeping excessively during the day and being restless at night — is a feature of canine cognitive dysfunction (doggy dementia).
- Lethargy has lasted more than 48 hours without a clear benign explanation
- The dog cannot be roused to normal alertness
- Any other symptom accompanies the increased sleep
- The dog is elderly with a sudden change in sleep pattern
- Gums appear pale, white, or grey