Whether your buddy’s an Olympic athlete reincarnated or a grade-A couch potato – it’s still pretty scary if you’ve suddenly got a lethargic dog on your hands. Lethargy in dogs is usually one of the first signs they’re struggling with a sickness, injury, infection, or just pain. (Yes, even if yours is a chill dog breed or a senior dog.) So if you’ve noticed your dog not moving much lately, here are all the reasons why – including how you can monitor your dog’s activity and vital signs to spot the signs of lethargy before they worsen. Let’s get started.

Is my dog lethargic…or just lazy?

Sometimes, when a dog isn’t moving a lot, it might just mean that you have a dog that’s on the more…well, relaxed side – temperament-wise. They may just need your help to get more active. Laziness in dogs doesn’t necessarily mean that your dog has a health issue. (Although it certainly can.) So keep an eye out if your dog is just being lazy – or if they show any other worrying signs of illness or distress.

💡Dogs tend to be creatures of habit – and they’ll mimic yours, since you’re their favorite person, after all. But luckily, even a few minutes of exercise per day can help both you and your dog built a routine that’ll set you both up for success. (Think like a 10-15 minute walk after meals to keep you both happy and healthy.)

Do I have a lethargic dog – or are they just tired?

A lethargic dog might be inactive and not show any interest in these regular activities. A tired dog might be on snooze mode – but they’ll still perk up when you call them over for, say, meals.

So before you start worrying about your dog’s sudden drop in activity, ask yourself:

  • Did the two of you just have a long walk or vigorous playtime together?
  • Is your dog just home from spending a day playing with other dogs – and now they just need a bit of rest?
  • Is your dog very young or very old? Both puppies and senior dogs might sleep a bit more than adult dogs. But usually, once you wake them up, they should be ready to engage.

⚠️ If your dog seems both tired and uninterested in regular activities together that they’d usually be excited to be a part of – they could be experiencing lethargy.

Is my dog just lazy?

Now if you’re wondering if your dog is simply…well, lazy, there are a few possible answers. While young puppies are often full of energy, many adult dogs tend to slow down with time. (Especially as they reach their senior years.) Dogs of both sexes also tend to become less active after being neutered, but not always. Some dog breeds are also just naturally more sedentary than others.

If your dog becomes lazy all of a sudden, this could be a sign of sickness or injury. Make sure to see your vet if that’s the case.

💡 A smart dog tracker can help you better understand how active your dog is under normal circumstances. I.e., when they’re healthy. So you can pick up on to a change in their activity and vital signs much earlier and get them to your vet for a checkup before their health takes a turn for the worse.

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Dealing with a lethargic dog: What it is & how to catch it early

What is lethargy in dogs?

Lethargy is the condition or quality of lacking energy; sluggishness, sleepiness, unresponsiveness or decreased interest in activity. Your dog might be showing signs of lethargy if you notice they’re no longer as excited to play fetch or go for walks – or simply stop moving all that much.

⚠️ Just as lethargy in humans can be a sign of illness, lethargy in dogs may indicate that your canine pal is unwell and might need veterinary attention.

How to catch on to your dog’s lethargy early on

Tracking your dog’s daily activity can potentially save their life. Vets even recommend keeping note of how well they’re able to keep up with you while out on a walk.1

sick dog laying in bed under sheets

“Keep track of your dog’s energy levels, especially how long they are able to walk.

If you notice significant declines, it could be a sign of pain, heart disease, or other illness.”

– VCA Animal Hospitals

When to see a vet

In general, it’s best to monitor your dog’s symptoms for around 24 hours – or a day – before you head to the vet. However, if you notice any of these signs – along with general lethargy – get your dog to a vet immediately:

  • Pale gums, which might indicate anemia or internal bleeding
  • A refusal to eat or a reduced appetite
  • Shaking, which might indicate your dog is experiencing some kind of pain
  • A distended abdomen, which might be a sign of bloating or another gastrointestinal disease
  • Labored breathing, which might indicate a respiratory infection
  • A discolored tongue (blueish or purplish)

All of these signs indicate an emergency – and the sooner your vet can check up your dog, the better.2 Your vet will perform a health check to rule out any potential illness or injury. Dogs who are lethargic may be suffering from one or more of the following health issues.

Causes of lethargy in dogs

If your dog is experiencing unusual weakness or lethargy, it could be caused by a wide range of factors. Some medication might include lethargy as a side effect. Else, it could be due to:

  • Parvovirus
    Which is spread through contact with infected dogs or contaminated surfaces. (Common if you board your dog frequently.) It affects your dog’s gastrointestinal tract. If your dog hasn’t been vaccinated or is under 4 months old, they’re at a higher risk.
  • Distemper
    Which is a virus affecting your dog’s respiratory, gastrointestinal, and nervous systems. It’s spread via the air and initially causes watery, pus-like discharge from their eyes.
  • Kennel cough
    This infectious bronchitis affects the respiratory system in dogs, causing them to cough.
  • Heartworms
    Caused by a parasitic worm that infects the heart, lungs, and blood vessels of the affected animal. Left untreated, heartworms can lead to caval syndrome which can cause organ failure and death.
  • Leptospirosis
    Caused by the bacteria Leptospira. It affects the kidney and liver in dogs and can lead to organ failure.
  • Lyme disease
    A tick-borne illness caused by the bacteria Borrelia burgdorferi that can affect both dogs and humans. The bacteria inside a tick is transmitted into the dog’s bloodstream from a tick bite and can travel to different organs, causing illness and ongoing health issues.
  • Chronic diseases
    Including liver disease, cancer, diabetes, hypothyroidism, or low blood sugar. Senior dogs and puppies under 4 months are at higher risk.
  • Poisoning
    Many common household substances, like pain relievers, are actually toxic to dogs. So if your dog’s swallowed these by accident, they may appear lethargic or sick – if they’ve been poisoned.

⚠️ If you suspect your dog has consumed anything that might be toxic, contact your vet or Animal Poison Control immediately. Here are a couple of emergency numbers:

CountryAnimal poisoning emergency hotline
US888-426-4435
UK01202 509000
Canada855-764-7661
Australia1300 869 738
New Zealand0800 869 738 

Other causes of lethargy in dogs

Besides these medical conditions, a lethargic dog may be experiencing:

  • Neurological diseases
    Including epilepsy, inflammation, or even brain tumors.
  • Pain
    Arthritis in senior dogs tends to cause them pain while moving around. So they may grow reluctant to go on walks or play together with time.
  • Trauma
    Much like humans, sadly, dogs can also experience complex conditions like Post-Traumatic Stress Disorder (PTSD) and depression. Which may come across as a lack of interest in regular activities.
  • Growing pains
    Puppies under 4 months have livers that can’t increase their blood sugar yet (since they’re still small). So they might experience low blood sugar, which can cause them to feel tired and out of sorts.

How to watch out for lethargy in dogs

Even with all the information above, it can be hard to determine the exact cause of lethargy in your dog by yourself. But here are a few steps to get started:

  • Inspect your dog for injuries
  • Take note of all the symptoms your dog is experiencing.
  • Are they just a little bit lazy (perhaps they’ve been indoors too much)?
  • Or do they also show worrying signs of a health issue, such as vomiting or diarrhea?

Anytime you suspect sickness or pain in your dog, it’s a good idea to take them to the vet. The treatment for your lethargic dog will depend on what’s causing it in the first place.

Once you’re at your vet’s, they’ll run some tests to determine the cause of your dog’s lethargy. Plus, they’ll know best how to treat it – and advise you how to best manage it to get your buddy feeling their best again.

Where a smart dog tracker can help

Tracking your dog’s daily activity can be a lifesaver. But let’s admit it: it can get a bit tedious over time too. That’s where a smart dog tracker can do all the hard work and monitoring for you – and provide you actionable data to figure out when to head to your vet. Including tracking your dog’s daily activity and even vital signs, like their breathing and heart rate.

Dog wearing white Tractive GPS Dog Tracker outside in a field, Tractive GPS app screens in the foreground

With its built-in motion detector, your trusty Tractive device logs in your dog’s every move – both over where they’re wandering, but also how often they’ve been active. Which, with time, can help you figure out:

  • How much is a “normal” level of activity for your dog.
  • How active your dog is compared to other, similar dogs of their age and breed
  • When there’s a dip in your dog’s regular activity – which might signal the beginnings of lethargy.

With this data at hand, you’re more likely to have a productive conversation with your vet – and spot potential health issues that much quicker.

Get health alerts for your dog

Our pups can’t always tell us if something’s wrong. But if their tracker detects unusual changes in their routine, you’ll get an alert, helping you catch potential issues early.

Shop Dog Trackers

And if you’ve liked this post, share it with a friend or a loved one – and let’s help build a safer, kinder world for our furry friends together.


Your furry friend’s health and wellbeing means as much as to us as it does to you. So we’ve made it a priority to only share medically-relevant content on our blog.

This post was checked, double-checked, and medically verified by Georgia-based vet, Dr. Dwight Alleyne.

Dr. Dwight Alleyne, DVM

Originally from Long Island, New York, Dr. Alleyne began his career at a no-kill animal shelter before becoming a licensed veterinary technician. He graduated from Cornell University Veterinary College in 2006 and completed an internship at Purdue University.

Now practicing in Georgia, Dr. Alleyne specializes in soft tissue surgery and ultrasounds. He also writes pet health articles on his website, “The Animal Doctor Blog” (www.anmldrblog.com).