What should I do about my dog’s rapid weight loss?

By: Ernest E. Ward, Jr., DVM

My dog’s weight loss doesn’t seem right. What’s happening?

If your dog’s rapid weight loss is worrisome, be sure to call your vet.

If your dog’s rapid weight loss is worrisome, be sure to call your vet.

  • Weight loss in dogs are associated with many normal and abnormal conditions.
  • Changes in diet, environment, or stress levels, including the addition of new pets, may lead to weight loss that’s rarely permanent or significant.
  • In addition, certain conditions and diseases can cause weight loss. Many of these conditions can be successfully treated once they’re diagnosed (see below).
  • To be clinically significant, the weight loss must exceed 10% of the normal body weight and not be associated with fluid loss or dehydration.

What’s causing my dog’s weight loss?

Weight loss, or an insufficient caloric intake relative to your dog’s body requirement, may be caused by:

  • Non-medical reasons such as excessive physical activity or prolonged exposure to a cold environment; inadequate or poor quality diet, or an insufficient quantity of food intake associated with anorexia, swallowing disorders or regurgitation.
  • Diseases and other medical conditions such as:
    • Anorexia due to a behavioral condition or disease
    • Pseudoanorexia caused by loss of smell, inability to grasp or chew food, swallowing disorders, vomiting or regurgitation
    • Malabsorptive disorders that inhibit the body’s ability to absorb nutrients from the intestinal tract
    • Digestive disorders that interfere with turning food into usable nutrients, such as exocrine pancreatic insufficiency
    • Metabolic disorders such as diabetes mellitus, (Addison’s disease, hyperthyroidism or hypothyroidism (rare in dogs, common in cats), and cancer
    • Diseases involving the major organs (heart, liver or kidneys)
    • Neuromuscular disease resulting in weakness or paralysis
    • Central nervous system disease causing depression, anorexia or pseudoanorexia
    • Pregnancy or lactation

What signs should I look for that warrant a call to my vet?

Any unusual weight loss should be reported to your vet. Jot down the answers to these questions before you call:

  • Is your dog’s appetite normal, increased or decreased?
  • What kind, when, where and how much dog food are you feeding your dog?
  • How and where do you store your dog food?
  • Does your dog have any trouble swallowing?
  • Have you observed any regurgitation or vomiting, diarrhea or loose stools, or changes in water consumption or urination?
  • What color and consistency are your dog’s stools?
  • Has your dog been spayed or neutered?
  • Does your dog have a fever?
  • How often do you administer your dog’s heartworm preventive? What type of preventative do you use?

How can the cause of my dog’s weight loss be diagnosed?

Your veterinarian will perform a thorough medical history and physical examination to determine which diagnostic tests to run. Blood and urine tests and radiographs (x-rays) are the most commonly recommended tests.

What can be done to treat my dog’s weight loss?

Once your veterinarian makes a diagnosis, treatment can be prescribed to resolve the problem or improve your dog’s quality of life.

What is the prognosis for my dog’s weight loss?

Until your veterinarian has a diagnosis, it’s hard to know exactly. First, your veterinarian will conduct a thorough medical history, complete physical examination and appropriate diagnostic testing to determine the prognosis and best treatment plan.

The good news is – your veterinarian can start getting answers for you right away.

Call your vet now to schedule an appointment.

Vet Written

Written by:
Ernest E. Ward, Jr., DVM
© 2014 MyPetED (Lifelearn Inc.). Used and/or modified with permission under license

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