Symptoms To Watch For In Your Dog: Unexplained Weight Loss

Weight loss is one of the potentially quiet symptoms that I find quite scary. If your dog has been overweight, you might welcome that the pounds are coming off. But unless it’s happening on purpose and you’re taking steps for your dog to lose some weight, such as increased exercise, changes in lifestyle and diet, please do take note.

Symptoms To Watch For In Your Dog: Unexplained Weight Loss

There are two potential problems with weight loss. 

When it happens too rapidly and when it happens without a known reason. And, of course, both can occur concurrently.

Unless you can think of an explanation after re-evaluating potential changes in your dog’s routine, feeding, and exercise schedule, it is time to see a veterinarian.

Even if your dog is losing weight but still has a good appetite.

Then there are situations when it gets even trickier. One of my friends was trying really hard to get her dog to lose some weight. They were struggling with the dog acting as if she was constantly starved and yet not shedding a pound. Then, finally, yet another diet plan apparently solved both issues and the weight started coming off. Couple weeks ago the dog suddenly died from aggressive lymphoma. Was there a connection between the weight loss and the disease? Nobody will ever know for sure.

If there is loss of appetite, vomiting or diarrhea, such signs can explain the weight loss but you, clearly, still have a problem you need to figure out and address.

Other signs that might accompany unexplained weight loss include lower energy level or lethargy, skin and coat changes, changes in drinking habits and urination

My rule of thumb is that whenever something is happening that shouldn’t, or without a good reason, I see a vet.

You should be particularly concerned when the weight loss exceeds ten percent of normal body weight.

A number of things can cause weight loss.

Inadequate or poor quality diet, reduced appetite, maldigestion or malabsorption of nutrients, metabolic issues, loss of nutrients such as due to diarrhea, vomiting or renal disease, or increased requirement of calories such as neoplasia. Specific causes might include parasites, dental disease, liver disease, kidney disease or failure, chronic partial GI obstruction, an intestinal disease such as inflammatory bowel disease (IBD), chronic infections, protein-losing intestinal disorder, diabetes, hyperthyroidism, cancer, heart disease, Cushing’s disease, Addison’s disease …

The list of possibilities is quite long.

Sometimes, what you might see as simple weight loss can be a sign of something slightly different. 

A generalized loss of muscle mass, not just fat, is usually a sign of more serious diseases such as kidney failure, liver failure, heart disease, or cancer.

If the bony prominences along your dog’s spine and skull are more visible than they used to be, make an appointment with your veterinarian immediately.

If my dog started losing weight without my trying to get them to lose some, or started losing weight fast, I’d most definitely start by getting a thorough physical exam, fecal testing, a urinalysis and full blood panel and go from there.

Sometimes getting to the root of the problem is relatively simple, at other times advanced diagnostic testing might be necessary, but working with a trusted veterinarian should give you at least some of the answers you need to improve your dog’s condition.

Related articles:

Symptoms: Recognition, Acknowledgement And Denial
Symptoms To Watch For In Your Dog: Excessive Panting
Symptoms To Watch For In Your Dog: Excessive Drinking
Symptoms To Watch For In Your Dog: Bad Odor 
Symptoms to Watch For In Your Dog: Excessive Drooling  
What Can Your Dog's Gums And Tongue Tell You? 
Symptoms To Watch For In Your Dog: Coughing 
Symptoms To Watch For In Your Dog: Excessive Head Shaking  
Symptoms To Watch For In Your Dog: What Is That Limp? 
Symptoms To Watch For In Your Dog: Nose Bleeds (Epistaxis)
Whats In The Urine? (Part I: What You Can Notice On Your Own)
What's In The Urine? (Part II: Urinalysis)
A Tale of Many Tails—and What Came Out From Underneath Stories from My Diary-rrhea (part I)
Acute Small Intestinal Diarrhea
Acute Large Intestinal Diarrhea (Acute Colitis)
hronic Large Intestinal Diarrhea
Chronic Small Intestinal Diarrhea

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Symptoms to Watch for in Your Dog

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  1. very informative. The list of things that can cause weight loss is quite alarming. It makes me want to weigh my dogs regularly which I haven't done/

    1. I believe that a weight loss that is of concern is also weight loss that can be seen with bare eyes.


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