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Why is my senior dog losing weight so fast without other symptoms?

Updated on September 23rd, 2025

Pet's info: Dog | Silky Terrier | Male | unneutered | 12 lbs

I have a 16 year old Australian silky terrier, who has lost 0.5kg in 2 days, which is a large amount , since he started with being 5.7kg. I am aware that this can lead to major sicknesses, but he has shown no other symptoms, and his lifestyle has not changed. Any idea the issue?

2 Answers

Most Helpful Answer

Answered By Rodrigo Roca, DVM

Veterinarian

Published on July 31st, 2017

Hello, this may be associated to volume/water loss or decreased intake which is the fastest contributor to weight that the body can lose/gain. I would monitor his urination and drinking habits. At 16 years old, which by the way is amazing, I would be most worried about his kidney function or an endocrine problem causing increased water loss. Also, if he isn't drinking as much, he may be running a little dry. Hope this helps.

1Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Jennifer Summerfield, DVM CPDT-KA
Veterinarian, Certified Dog Trainer
Published on December 31st, 2016
Poor Jackson! It does sound like something isn't right. Some common causes of weight loss along with excessive water consumption in a dog this age would include chronic kidney disease, diabetes or Cushing's disease. It would be helpful to know specifically what lab tests have been done and what the results were, since some of these issues don't necessarily show up on routine lab work. Feel free to post another question with more details, or request a consultation with one of us for a more in-depth discussion if you prefer - we would be happy to try and give you some more specific suggestions.
1Pet Parents found this answer helpful

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