If your dog is slowing down, acting tired, or refusing to play like he used to, chances are he's not simply being lazy. Pets who act lethargic or show signs of exercise intolerance may have a serious underlying condition. In particular, this may be caused by a serious condition like heart disease. If your dog is acting lethargic or is simply less active than usual, it's important to pay attention to these cues. Keep reading to understand why your dog might be exercise-intolerant and what you should do about it.
Possible Causes of Lethargy
It's normal for some dogs to slow down a bit after heavy activity. For example, your dog may want to spend a day or two sleeping more than usual following a long day at the dog park or a rigorous hike. However, prolonged tiredness should not be ignored. Exercise intolerance is only one red flag for major issues like heart disease, but it could also signal a host of other problems, ranging from mild issues, such as muscle pain, to serious conditions like congestive heart failure. Vets Now lists several potential reasons why your dog is acting lethargic:
- Infection or illness, including parvovirus or kennel cough
- Heart problems
- Liver problems
- Diabetes or hypoglycemia
- Hypothyroidism
- Parasites
- Side effects of medication
- Poisoning or trauma
The walking service and dog advice site, Wag!, adds that exercise intolerance in combination with other symptoms—such as a lack of appetite, coughing, or fainting—could also be a sign of pulmonary hypertension (high blood pressure in the lungs) or other cardiovascular disease.
Signs of Exercise Intolerance and Lethargy in Dogs
It's usually fairly easy to tell if your dog is acting sluggish. Excessive sleep, low energy, lack of excitement, and delayed responses are all overt signs of a lethargic dog, says Vetinfo. Exercise intolerance can be harder to spot, especially if you don't walk or play with your dog regularly. In milder cases, says Wag!, your pooch may simply not want to walk as far or play as much as normal. Coughing, heavy panting, or labored breathing following physical activity might also signal exercise intolerance. Extreme cases might involve confusion, disorientation, a lapse in toilet training, a rise in body temperature, wobbliness, and even collapse.
Once at the vet, your dog will be thoroughly examined. The vet will likely look for any signs of lameness, injury, or pain, as well as any possible tumors. He or she will also perform blood and urine tests to check for underlying health conditions. It's likely that your pup will also be hooked up to an electrocardiograph machine to check the electrical activity of his heart, and will be given chest x-rays to examine his heart and lungs. Your vet might also recommend an ultrasound, CT scan, or MRI to help diagnose your pup's condition. You can help achieve a proper diagnosis by providing your vet with a list of any medications your dog takes, talking over the details about his diet and lifestyle, and mentioning any other symptoms or changes you've noticed in your pup.