Lethargy in Dogs: When is it an Emergency?

Dr. Enio Sanmarti

Jun 29, 2021

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Is your dog lethargic? Are you getting worried about him? Lethargy is a common symptom in dogs, but how do you know when it’s something that requires an emergency vet visit?

In the article below, we’ll walk you through everything you need to know about lethargy in dogs. You can use this information to figure out when it’s time to see a vet right away and when you might be able to wait.

What is Lethargy?

Lethargy can sometimes be described as extreme tiredness, although it isn’t quite the same. A lethargic dog is not interested in his/her normal day-to-day life and is either unable or unwilling to get up out of bed very often. He/she may be weak and unable to move well, or he may be stiff and in a lot of pain when he/she moves.

A lethargic dog usually won’t show much interest in food, treats, or a favorite toy. He/she may watch the household move around him/her but won’t engage. He/she may be alert or only partially alert, depending on the severity of the lethargy.

What Conditions Have Lethargy as a Sign for Dogs?

In short, almost every dog ailment or condition can have lethargy as a sign, and this is why it’s crucial to pay attention to other signs your dog might show at the same time. If your dog is lethargic with no other symptoms, for example, she may simply have overtired herself on a long walk or playing at the dog park, or she might be too hot but not yet at the point of heatstroke. But if she has other symptoms, they can help you pinpoint the cause of the lethargy.

Common Conditions

Some conditions that can have dog lethargy as a common symptom include:

  • If your dog becomes injured in some way, such as a broken bone
  • Stung or bitten by a poisonous insect or snake
  • If your dog is in pain
  • Suffering from arthritis
  • Cancer
  • Organ disease
  • Diabetes
  • Ingestion of toxic substances or other common dog poisons
  • Digestive system problems
  • Hypothyroidism
  • Internal parasites
  • Eye problems
  • Neurological disorders
  • Dehydration

These are just some of the multitude of conditions that can cause lethargy to present as a symptom in dogs, and as you can see, the vast majority of problems can potentially lead to a lethargic dog that will require further vet care and attention.

Severe Conditions

Sadly, a dog may become lethargic when he is about to die as well. However, this type of lethargy is quite different and is usually a sign of a dog who is not able to move even if she/he wants to. She/he may try to get up but can’t, or she/he might show interest in her/his food but be unable to make it all the way over to her/his food dish. If your dog is lethargic and also showing signs that she/he is struggling to breathe, this may mean that she/he is about to die.

When is Lethargy in Dogs a Cause for Concern?

Lethargy is a cause for concern when it is moderate to severe. For example, if your dog is so lethargic that nothing gets his attention, then this is probably severe lethargy and will require an immediate visit to the emergency vet.

On the other hand, if your dog is fairly lethargic but will still pay attention or try to get up if you offer him his favorite treat, this is probably moderate lethargy. He might still need an emergency vet depending on his other signs, but he might be able to wait for his regular vet. Never hesitate to speak to a vet or emergency vet if you’re unsure about what to do for your dog.

If your dog’s lethargy is mild, he probably doesn’t need to see a vet at all, and he certainly doesn’t need to see an emergency vet. Mild lethargy may occur in dogs who overexert themselves, especially in hot weather. They may be sound asleep for a long while and may not rouse, but when they do wake up again, they usually feel fine and behave like they normally do. A dog with mild lethargy probably just needs to sleep off whatever is causing the problem, but you can certainly contact your regular vet if you feel it’s best to do so.

Don’t Hesitate to Seek Veterinary Care for Your Lethargic Dog

As you can see, there is a lot to keep in mind if your dog is lethargic. Sometimes, this problem is a sign of nothing more sinister than a dog who has had too much exercise on a hot day. However, at other times, it can be a symptom of a much more serious underlying problem that needs your attention as soon as possible.

If you think your dog is more lethargic than he should be given his recent activity, you should take him to the vet for a complete checkup. And if he is lethargic along with other signs, you may want to consider taking him to the emergency vet instead.

At VEG, when you call any one of our locations, you’ll always speak directly with an emergency vet who will be able to provide advice on what would be best to do for your pet. When it comes to your dog’s health, you always want to err on the side of caution, especially if you suspect something might be wrong. If you think your pet is suffering from a more serious case of dog lethargy, call a vet or emergency vet right away so your pet can get the care they need as soon as possible.