Dog tired and listless: seven causes and when to call

Reading time 6 min · Level 1: Why the symptom happens

The short answer: A dog that is tired after a long day, a hot day or a vaccination is usually back to normal within a day. A dog that is listless for no reason, will not eat or is getting worse is something else. Tiredness is one of the least specific symptoms there is and can be caused by anything from fever and tick-borne infection to poisoning, uterine infection and hormonal disease. Take its temperature, look at the gums and call the vet if your dog is not itself within a day. If it is very unwell, go straight away.

Normal tiredness or a sign of illness

All dogs have quiet days. After a long hike, a swim in the heat, a busy weekend with guests or a vaccination, a dog may sleep more than usual without anything being wrong. Normal tiredness has an obvious cause, the dog eats and drinks, responds when you say its name and is itself again the next day.

What separates illness from tiredness is that the dog's general condition is affected. It does not greet you when you come home, stays lying down when the lead comes out, withdraws or ignores its food. That tiredness has no obvious explanation and it persists or gets worse.

Do a quick check at home

It takes two minutes and gives the vet far better information when you call.

Do not feel the nose. A warm or dry nose says nothing about fever; the only way to know is a thermometer¹.

Seven common causes

1. Fever and infection. Fever makes dogs listless, just as it does people. Behind it there is usually an infection somewhere in the body: airways, urinary tract, a tooth, a wound or an abscess.

2. Tick-borne infection. Anaplasmosis is spread by the common tick and often causes fever, lethargy and reduced appetite, sometimes with stiffness and soreness. Symptoms appear roughly one to two weeks after the bite². If you have removed ticks from your dog recently, tell the vet.

3. Uterine infection (pyometra). Affects unspayed females and is more common than many people think. A Swedish study of insured dogs found that about one in four bitches had had pyometra before the age of ten³. It typically comes a few weeks after a season and causes tiredness, increased thirst and sometimes discharge. It is an emergency that needs treatment by a vet.

4. Poisoning. Symptoms do not always appear at once. The dog may become tired and listless, develop a fever, stop eating or get pale gums, which is seen among other things after rat poison⁴. If your dog may have got at rat poison, medicines, chocolate, raisins or antifreeze, call the vet at once, even if it seems fine.

5. Pain. A dog in pain moves less and may look tired rather than ill. It may be a joint, the back, the stomach or a tooth. Stiffness when getting up and reluctance to jump into the car are clues.

6. Hormonal disease. An underactive thyroid develops slowly. The dog may seem old before its time: tired, cold, slow on walks and heavier⁵. Here the tiredness creeps in over months rather than appearing suddenly.

7. Heart, blood and internal organs. Anaemia, heart disease, kidney and liver disease and diabetes can all start with a dog that has less energy. There are often other signs: coughing, rapid breathing, increased thirst, weight change. That is why the vet so often takes a blood test when a dog is listless without an obvious cause.

When to see the vet

Urgently, straight away: if the gums are white, yellow or bluish, if the dog is breathing with effort, collapses, is hard to make contact with, has a swollen belly or retches without bringing anything up. If it may have swallowed something poisonous. If an unspayed female is tired and drinking a lot after a season. If the dog has a high fever or an abnormally low temperature and is also unwell.

The same day or the next: if the dog has a fever, will not eat, has been tired for more than a day without explanation or is also vomiting, has diarrhoea, is coughing or limping. According to AniCura, a dog should see a vet the same day with acute fever plus painful lameness or a markedly affected general condition².

Within a few weeks: if the dog is gradually managing less, putting on weight, feeling the cold or seems to be ageing faster than it should. Creeping tiredness is easy to dismiss as age, but it is often the kind there is most to be done about.

What you can do yourself

Let the dog rest with water nearby. Offer a little food, but do not force it.

Measure and make notes. Temperature morning and evening, how much it eats and drinks, urine and stools. A few lines on your phone are invaluable to the vet.

Find out what is normal. Measure temperature and breathing once when your dog is healthy and rested. Then you know what you are comparing with next time.

Do not give your own medicines. Human painkillers can be dangerous for dogs. Anything like that goes through the vet.

Go through the coat. Look for ticks, wounds and swellings. Remove ticks as soon as you find them.

Frequently asked questions

Why is my dog tired after a vaccination?

It is common for a dog to be a little tired and sometimes have a mild fever for a day after vaccination. If it gets worse, stops eating or gets swelling of the face, call the vet.

Can dogs get tired from the heat?

Yes. Many dogs are calmer on hot days. But a dog that pants heavily, drools a lot, becomes wobbly or cannot be cooled down may have heatstroke, which is an emergency.

Is it normal for an older dog to sleep more?

Older dogs do sleep more, but a clear change over a few weeks or months is worth a check. Pain, the thyroid and the heart are common explanations that can be investigated.

How long can I wait with a tired dog?

If the dog is eating, drinking and has a normal temperature, you can wait a day and see if it improves. If any of that is not the case, or if you feel unsure, it is better to call once too often.

That was the short answer. If you have a question about your own pet, email us at info@herbiovet.se. We reply within one working day.