my dog is lethargic and not himself
Pet Health Questions and Answers

Why Is My Dog Sleeping a Lot More Than Usual?

Dogs provide us with so much joy, laughter, and love. That’s why, when your dog is behaving strangely or seems unwell, it can be quite worrying. Our furry friends can’t speak to us when something is wrong, after all. It’s down to us to try and put the pieces together.

As a general rule, dogs are active, lively animals. If your dog has gone from being a bundle of energy to lethargic and lazy, you might be wondering “why is my dog sleeping so much all of a sudden?”

There are many different reasons why your dog might be lacking energy, and they’re not always straightforward. Some are more serious than others. It’s time to familiarize yourself with the potential causes of excessive sleepiness, and what to do about them.

In this guide, we’ll go through the most common reasons why your dog might be sleeping too much. By the end, you’ll have a better idea of what the problem is, and how to fix it.

Table of Contents:

How Much Does a Dog Sleep In a Day?

If you’re new to the world of dog ownership, you might not realize just how much dogs sleep. It’s a good idea to get to know how much sleep is normal for your pup. That way, when their habits change, you’ll be quick to realize there’s a problem.

Humans, on average, need about 7 to 8 hours of sleep per night. We normally sleep in one long chunk and are awake throughout the rest of the day. Dogs, on the other hand, are a different story. Dogs spend around 12 to 14 hours per 24-hour period sleeping. This amount can vary due to individual differences, but it’s a good average figure for most dogs.

That equates to about 50% of their day. If you’re not used to it, it can be worrying to start with, but dogs sleeping half the time is actually normal. Of the time they’re awake, dogs are only active and energetic for about half of it. The rest of the time, they’re awake but resting – sitting or lying down.

Furthermore, dogs don’t usually sleep all in one go. Usually, they do spend 8 hours per night asleep with you, but the rest of their sleep is taken in naps throughout the day. Everybody needs some nap time!

So, if this sounds like your dog, you probably have nothing to worry about. These are normal, healthy sleeping habits. However, if your dog is sleeping significantly more than this, there might be a problem.

Why Is My Dog Sleeping So Much All Of A Sudden?

Different dogs vary in how much they sleep, just like humans do – but a change in the amount your dog is sleeping can be a cause for concern. If your dog is sleeping a lot more than usual, there could be many explanations – some more concerning than others.

Illness is the first thing to look out for when your dog is sleeping a lot. Many illnesses can cause lethargy or excessive sleeping as part of their symptom set. If illness is the reason, you’ll probably have noticed other symptoms as well.

Below, you’ll find a list of the most common illnesses which cause your dog to sleep too much. If it seems that your dog sick and is sleeping a lot, it’s probably one of these issues causing it.

my dog seems sad and tired


The thyroid is a gland in the body which produces hormones that are essential for maintaining a normal working metabolism. Hypothyroidism is a condition which results in the thyroid gland not producing enough of these hormones. As a result, your dog’s metabolic function will be decreased, and they’ll seem quite sick.

Hypothyroidism is most common in dogs which are slightly older – between 4 and 10 years old. If your dog is young, it could still be hypothyroidism, but it’s less likely. It’s also more common in larger dogs than smaller ones.

There are also certain breeds which are more predisposed to the condition. The most susceptible of these breeds include golden retrievers, Labradors, Great Danes, Greyhounds, dachshunds, boxers and Doberman pinschers.

Other than lethargy and excess sleep, the main symptoms of hypothyroidism are:

  • Skin problems, such as infections and dry skin
  • Coat problems, such as dryness, dullness or hair loss
  • Weight gain
  • Slow heart rate
  • Mental slowness
  • Poor tolerance to cold
  • Muscle weakness

If you notice any of these symptoms and your dog is sleeping a lot, hypothyroidism could be the cause.


Diabetes is a disease which is seen in both humans and dogs. In diabetes, the body does not produce the hormone insulin, or the body does not respond to insulin. Insulin is necessary because it carries glucose (sugar) from the blood into the cells of the body. If there isn’t enough insulin, or it doesn’t do its job, the blood sugar can elevate. This is hyperglycemia and can be dangerous.

If diabetes develops in dogs and is left untreated, it can cause lots of serious health problems or even death. Fortunately, once diabetes is diagnosed, it’s usually fairly easy to manage. Dogs with diabetes can often live normal lives once their diabetes is under control.

Certain breeds are more prone to diabetes than others. These breeds include Schnauzers, Dachshunds, Poodles, Australian terriers, Samoyeds, and Keeshonds.

If your dog is sleeping a lot and seems lethargic, diabetes could be the cause. If it’s diabetes, you’ll probably notice these other symptoms too:

  • Increased thirst, drinking a lot
  • Excessive urination
  • Increased hunger
  • Weight loss
  • Vomiting
  • Urinary tract infections
  • Sweet-smelling breath (like pear drops)

If you notice these symptoms along with tiredness, take your dog to a veterinarian for a blood test.

why does my dog sleep so much during the day?


Anemia isn’t actually a disease in and of itself. It’s actually a medical phenomenon which can have lots of different causes. If your dog is anemic, it means their blood has a reduced number of red blood cells, hemoglobin, or both.

Excessive sleeping is the main symptom of anemia in dogs, but it isn’t the only indicator. If you think that your dog might be anemic, check their gums. A dog’s gums should usually be bright pink. With anemia in dogs, they can appear pale pink or even white in color. An anemic dog might also experience difficulty exercising and may have a decreased appetite.

Anemia can be triggered by blood loss, the breakdown of red blood cells, or reduced production of red blood cells. Each of these problems has various different causes.

The most common are as follows:

  • Blood-sucking worms and parasites, such as ticks, fleas, and hookworms
  • Parasites in the blood, such as heartworm
  • Autoimmune disorders
  • Tumors in certain areas of the body, such as the kidneys
  • Blood clotting disorders
  • Damage to blood vessels or internal organs due to injury

If you suspect that your dog might be anemic, take them to a veterinarian. They’ll be able to run a blood test to confirm it.

Viruses And Bacteria

Sometimes, certain infections can cause a dog to become excessively sleepy. These infections can be either viral or bacterial in nature. If your dog has a viral or bacterial infection, they’ll display other symptoms of illness too, and will seem very sick.

The most common viral and bacterial infections in dogs are:

  • Parvovirus is a contagious, serious illness. It’s caused by a virus which hampers the body’s ability to absorb nutrients and fluids. The symptoms to look out for include lethargy, fever, vomiting, weight loss, diarrhea and reduced appetite. You might also notice that your dog has a fast heartbeat, a painful stomach, and red eyes.
  • Distemper. Similar to parvovirus, distemper is a serious, contagious viral infection. Distemper shares many of the same symptoms as parvovirus, but can also cause coughing, and watery discharge from the nose and eyes. Occasionally, it can also cause the pads of the feet to become thicker.
  • Kennel cough, also called infectious tracheobronchitis, is a viral respiratory. Kennel cough is more common during the summer months, and is contagious. The main symptom of kennel cough is a persistent, loud cough which can last for up to two weeks.
  • Leptospirosis. This is an infection caused by bacteria, which can be transmitted through a contaminated water source or soil. As well as lethargy, dogs with leptospirosis may display fever, vomiting, diarrhea, muscle pain and blood in the urine.

Infections can be very serious if not treated, so if your dog displays any of the above symptoms, seek medical help for them.

Organ Diseases

Diseased organs can also cause dogs to become tired and sleep more often. This is because they often have a lack of energy due to the disease, and they’re often in a lot of pain. Dogs in pain tend to sleep as much as they can.

Excessive sleep can be due to problems with the following organs:

  • Kidneys. If your dog has kidney failure, it can cause lethargy and over-sleeping. You might also notice increased drinking and urination, appetite loss, weight loss, vomiting, or blood in the urine. Some dogs with kidney problems also have a chemical smell to their breath and may stumble when walking.
  • Dogs with heart disease will display fatigue and listlessness, causing them to sleep more. They may also have difficulty breathing, walking and exercising. You might also notice weight loss, a lack of appetite, a bloated abdomen, or trouble sleeping.
  • Liver disease in dogs can also result in excessive sleeping and lack of energy. Other than this, symptoms of liver disease include jaundice (yellowing of the eyes and skin), disorientation, personality changes, seizures, vomiting and diarrhea, and weight loss.

Of course, diseases of the vital organs are extremely serious and shouldn’t be taken lightly. If your dog matches the above symptoms, they’ll need to be seen by a veterinarian.

dog sleeps all day and won't eat


Finally, your dog may be sleeping a lot because they’ve eaten something they shouldn’t. Poisoning in dogs can be mild, but it can also be quite serious. It all depends on what the toxin is.

Dogs are smart, but they have a tendency to eat whatever they can find, even if it’s not good for them. Antifreeze, for example, tastes sweet, so dogs (and cats) tend to drink it if they find a puddle of it on the ground. If you have toxic mushrooms or toadstools growing in your yard, your dog could have eaten one of those. Rat poison and slug or snail killer can also be very toxic.

Chocolate, alcohol, coffee, garlic, onions, walnuts, grapes, and avocados are also poisonous to dogs. In fact, there are many foods which are perfectly safe for humans but can be deadly for our canine friends. If your dog has eaten any human food, whether you gave it to them or they got into a cupboard, it could be making them ill.

The early signs of poisoning in dogs, other than lethargy and sleeping a lot, are:

  • Appetite loss
  • Vomiting
  • Excessive drooling
  • Lack of coordination
  • Diarrhea
  • Labored breathing

As the poisoning progresses, your dog might also lose consciousness, have a seizure, become comatose or even die. If you think your dog might have been exposed to a toxin, your veterinarian will know what to do. Don’t try to induce vomiting, because this can make it worse.

If My Dog Isn’t Sick, What Else Could It Be?

If your dog doesn’t seem to have any tell-tale symptoms of sickness, you might not be dealing with an illness at all. Dogs don’t always oversleep because they’re sick – there are many other reasons why your dog might be a bit tired.

It’s always a good idea to take your dog to a veterinarian, just to rule out illness. If they find nothing wrong, it could be one of the following factors.

Breed of Dog

Every dog breed is different. A golden retriever doesn’t look anything like a miniature dachshund. But, it’s not just appearance that plays a part in breed differences; each breed behaves differently, too.

The breeds of dog that we keep as pets today were all designed to do different things. Some, like the Border Collie, was designed to help out on the farm, herding sheep. Some dogs, though, were bred purely to keep humans company. Therefore, it’s no surprise that they all demonstrate different behaviors. Sleep habits are one such behavior which can be affected by breed; there are some dog breeds that sleep a lot, and some that don’t.

So, what factors determine which breeds sleep the most? Size tends to play a part. As a general rule, larger breeds of dog have the tendency to sleep more than smaller dogs. St Bernards, Mastiffs, Great Pyrenees and Newfoundlands all have the reputation of being “mat dogs” because of how much they sleep. They can spend up to 18 hours a day dozing.

Working dogs, who were bred to spend most of the day on their feet, often need to sleep a lot less. Such breeds include Collies, Dalmatians, Huskies, Retrievers, Beagles and Russell Terriers, among others.

Finally, dogs which were bred purely as “companion animals”, serving no working purpose, often tend to sleep more. These include the Cavalier King Charles Spaniel, Pekingese, Shih Tzu, and Pug.

what's wrong with my dog symptoms

Age of the Dog

Age is one of the main factors in determining how much sleep your dog will get. As dogs progress through their life, their need for sleep will change depending on how old they are. The general rule is that dogs sleep the most when they are very young, and when they start to get old.

Puppies (dogs under 1 year old) are extremely active and excitable, but only for short bursts of time. They spend almost all their time awake playing, and so tend to tire themselves out quite quickly. To replace this lost energy, puppies will sleep a lot more than adult dogs. This extra sleep also helps with their growth and development. Puppies can sleep for up to 20 hours a day, especially if they’re under four months old. They also tend to sleep much more deeply – so if you have a young dog in deep sleep hard to wake up, don’t panic!

You’d expect your puppy to need less sleep as he gets older, so if your puppy is sleeping more than usual it could be a sign of illness. On the other hand, he could just be going through an intense developmental spurt (physical and mental) and need more sleep as a result. Be on the lookout for other symptoms of illness, and consult your vet if you’re concerned.

Just like puppies, older dogs also tend to sleep more than adult dogs. Depending on which breed of dog you have, they reach old age at different times. Larger dogs, such as Great Danes, are considered senior from the age of 6. Chihuahuas, on the other hand, often aren’t classified as old until they’re 10 or 11.

When a dog is old, their energy levels aren’t what they used to be. Elderly dogs get tired a lot more easily than adult dogs and need to rest more as a result. They can also suffer from complications of age, such as arthritis, which makes them more lethargic.

Boredom Level

The environment in which your dog lives its life can play a huge part in how much it sleeps. Active, busy dogs are far less likely to sleep more often than is necessary. This is because activities which stimulate the brain will help keep it awake and alert.

If you are taking your dog on regular walks or giving it other activities to do, it probably isn’t a case of boredom. However, many dog owners don’t provide as enriching an environment as they should for their pooches. Dogs that are stuck inside a house or apartment for most of the day and don’t have any stimulation will often sleep because there isn’t anything better to do.

If you think your dog might be bored, there are things you can do. Firstly, make sure you take your dog on regular walks. When at home, provide your dog with toys and bones to chew on. If you have a yard, try playing fetch every now and then. You can also buy special balls which you can hide treats inside. These are great at keeping a dog entertained, while they try to figure out how to get to the reward.

Finally, dogs need mental stimulation as well. At least once a day, make sure to practice commands with your dog, such as sitting, shaking the paw and rolling over.


If you find your dog sleeping a lot and not eating, and illness isn’t responsible, it could be depression. Yes, it might sound unbelievable, but dogs can suffer from mental health issues just as we can. There can be many reasons why a dog might be depressed, but most of them have to do with a big change in the dog’s life.

Distressing events, of course, may lead to depression. These include the death or loss of a human in the household or another animal. Other big changes could include a new baby or pet, a house move or an injury. Your dog might also become depressed if you get a new job and start spending more time away from the home.

If your dog is depressed, you will notice them becoming lethargic and sleeping for a lot of the time. They might also stop eating or drinking as much. They might also show signs of anxiety, such as excessive chewing, barking or howling at night. Your dog may also seem less interested in things he used to love.

If you think your dog is depressed, it’s best to take them to the veterinarian so they can be sure it’s not something else. In the meantime, keep playing with and socializing your dog, and reward them when they show signs of happiness.

Poor Quality Dog Food

This last point is quite important, but something which dog owners often overlook. The main reason that a dog might sleep too much, regardless of the cause, is a lack of energy. Where do dogs get their energy? From the food they eat.

So, it makes sense that if this food is poor in quality, your dog won’t have the right amount of energy. Poor food leads to poor nutrition, which can affect your dog’s health in the long run.

Look out for dog foods which don’t contain a good quality source of protein in the first six ingredients. Avoid “by-product meal”, as this contains no muscle meat and is just bones, skin and entrails.  Some dog food brands use corn, grain and flour in abundance to bulk out the food – too much grain is bad for dogs and doesn’t provide them with good quality protein.

If you aren’t sure whether you’re using a good brand of dog food, consult your veterinarian.

What Should I Do If I’m Not Sure?

We’ve now been through the most common reasons that a dog might be sleeping more than usual. After reading this guide, you should have a good idea of what’s causing your dog to be so tired. Hopefully, your dog’s symptoms will match up with something you’ve read here, to help you figure out what the issue is.

However, dogs are all unique, and sometimes the answer isn’t as straightforward as you’d hope. If you aren’t sure exactly why your dog is sleeping excessively, you should take them to a veterinarian. They’ll be able to examine your dog, and run tests such as blood tests, to see if they can find anything wrong. That will give you the best chance of solving the problem, whatever it may be.

Is It Bad For A Dog To Sleep Too Much?

It’s not bad for a dog to sleep too much as long as it’s healthy, happy and active when it’s awake. Some dogs just like their sleep! It’s more sudden changes in the amount your dog sleeps that could be an indication of a problem.

My Dog Sleeps All Day When I’m Gone

It can be worrying when you leave your dog alone, come home, and he’s barely moved – but actually, this is unlikely to be a cause for concern as long as he’s happy and active when you’re around.

If your dog was bored, he’d be more likely to chew things (most likely things he wasn’t supposed to!) than to just lie there. Sleeping is also a good sign that he’s not anxious, or he’d be pacing or scratching at the door.

Remember: dogs can easily sleep for 12 hours per day or more, so even if he’s sleeping all night and the whole time you’re out, that’s not abnormal. He might just be saving all his energy for playtime when you’re back!

In the meantime, watch this cute video of puppies falling asleep.