What is Lethargy in Dogs? Explaining Why Your Pup Is More Dog-Tired Than Usual

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If your normally bouncy pooch is just lying around, chances are you're probably a bit worried. But there are a number of reasons why your dog is lethargic. Perhaps he's having a bad day or just feels tired from playing—or there could be something more serious going on. What's a concerned dog parent to do? You may be able to learn more by taking a closer look at your dog.

What Is Lethargy in Dogs?

The Merck Veterinary Manual describes it as a "lack of energy; apathy." If you crack open a dictionary, you'll find it means someone is abnormally tired or "lazy, sluggish, or indifferent."

Lethargy can look a little different in each dog. Pet parents often say, "My dog is not himself" or that their dog seems sad. You can also describe a lethargic dog as listless, lackadaisical, disinterested, sleepy, or dull. Veterinarians sometimes say a dog is "puny" when they act lethargic.

Dogs with lethargy may not show typical interest in food, treats, toys, and activities. They may sleep more often than usual or isolate themselves from people and other pets in the home. You know your dog better than anyone, so if your dog seems "off," there's probably something wrong.

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Lethargic Dog Signs and Symptoms

Lethargy is both a symptom and a sign. For the dogs, lethargy is a symptom: something they feel that indicates the presence of a disorder. To us, lethargy is an objective, observed sign that something is wrong. Because dogs can't tell us how they feel, we must rely on the signs they show us in order to figure out what's going on.

Lethargic dogs may experience additional symptoms. It all depends on the actual cause of the lethargy. You can observe your dog for other signs of illness that point to the underlying condition. Dogs with lethargy may show one or more of the following signs:

• Vomiting

• Diarrhea

• Poor appetite

• Weight loss

• Depression

• Anxiety

• Abnormal breathing

• Difficulty urinating or defecating

• Fever

• Coughing and/or sneezing

• Discharge from eyes, ears, nose, or mouth

• Itching

• Limping or walking abnormally

Here's What Might Be Causing Your Dog's Lethargy

Lethargy is a common sign of most health problems in dogs—both mental and physical. Think about it: When you feel unwell, isn't lethargy one of the things you experience? Conditions that cause pain or discomfort will often lead to lethargy in dogs. Other conditions simply drain your dog's energy. The following list is not exhaustive, but it includes many potential causes of lethargy in dogs:

• Exhaustion from exercise, play, or heat

• Fear, stress, or anxiety from a specific situation

• Generalized anxiety disorders

• Dehydration

• Heatstroke

• Arthritis

• Infection anywhere in or on the body (viral, bacterial, fungal)

• Heartworm disease

• Intestinal parasites

• Gastrointestinal issues

• Liver disease

• Kidney disease

• Pancreatitis

• Diabetes

• Hypoglycemia (low blood sugar)

• Hypothyroidism

• Bloat (gastric dilation volvulus)

• Cancer

• Injury

• Food poisoning or contamination (especially from food that's been recalled)

• Toxin exposure

• Bite or sting from a creature (like a snake or bee)

• Spinal conditions like IVDD

• Brain conditions like meningoencephalitis

Treatment for Lethargic Dogs

Lethargy itself is not a disease and has no specific treatment. Your vet will first need to diagnose the underlying cause of your dog's lethargy in order to determine the proper treatment. The vet will first do a physical examination to asses your dog's overall condition. This will include checking hydration, palpating the abdomen, looking at the mouth and teeth, listening to the heart and lungs, manipulating the joints, and looking at the skin and coat.

Many of the conditions that cause lethargy will require supportive care to help dogs feel better. Treatment may include fluid therapy and medications to ease symptoms. The vet may also prescribe medications that target a specific disorder. For example, bacterial infections typically require antibiotic treatment. Dewormers are used to treat intestinal parasites. Dogs may even require surgery if they are injured or have a serious condition like bloat.

A dog with a long-term or ongoing condition, like chronic kidney disease, may need to see the vet periodically because of bouts of lethargy. The vet will do an exam and run tests to determine what needs to be adjusted in the dog's treatment plan.

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My Dog Is Lethargic: Should I Worry?

Because lethargy is a very general sign, it can be difficult to know when it's urgent. It really depends on the severity of the lethargy and the presence of accompanying signs. When in doubt, call your veterinarian's office for advice.

If your dog is suddenly acting mildly lethargic without other signs of being sick, then you can observe your dog for about a day to see if he improves. Contact your veterinarian if the lethargy continues for more than 24 hours or if other signs develop.

Moderate to severe lethargy requires more immediate attention, even if you don't notice other signs of illness. Call your vet right away and report what you are seeing. They can tell you if need to bring your dog in right away or if it's safe to schedule an appointment.

It's an emergency situation if your dog is so lethargic that he's unresponsive or unable to get up. Bring your dog directly to the nearest open veterinary facility. If it's after normal business hours, head to a local animal emergency center. It's always a good idea to call the vet's office and let them know you're on the way.