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My cat lost weight in 3 days but eats normally. What's wrong?

Updated on September 23rd, 2025

Pet's info: Cat | Mixed Breed | Female | unspayed | 3 months and 23 days old

Hello, my cat lost some of her weight during these last 3 days but she has been eating normally, what may be the cause for this and what should I do? Thanks!

3 Answers

Most Helpful Answer

Answered By Daniel Fonza, DVM

Veterinarian

Published on October 26th, 2017

Hi there and thank you for using pet coach to address your concern. First, I would ensure that she is being fed the proper amount. Most foods will provide a feeding guide on the back of the food or can that gives you the most recommended feeding amount per age and weight. If you are already feeding an appropriate amount then I would recommend having her examined by a vet and have testing done such as a feline leukemia and feline aids test to ensure she is not positive for either and a general blood panel to check organ function and see if there is any indication there is an active infection. I hope this helps guide you in the right direction. Please let me know if you have any other questions or concerns. I am also available via consultation if needed.

1Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Destini R. Holloway, DVM
Veterinarian
Published on January 31st, 2017
I am so sorry to hear tat your pet Skye is in such poor medical condition. That is a lot of weight to lose and I am deeply concerned that her heart may not be able to take that level of weight loss much longer. She needs medical attention ASAP, because this could be something that is treatable, like hyperthyroidism. Other possibilities are intestinal parasites and cancer has to be considered due to your pets age and gradual weight loss.
I also am not sure how your pets appetite is or if she is having loose stool, causing her to not absorb the nutrients she needs. More information is needed here to make any more recommendations on how to proceed with your pet Sky's care. Perhaps a consultation will allow you to voice all your concerns and receive adequate advise for her.
1Pet Parents found this answer helpful
Answered By Dr. Elizabeth
Veterinarian
Published on March 7th, 2019
Pets with unexplained weight loss should always be checked out by their veterinarian. Parasites, kidney or liver disease and unfortunately, cancer are potential causes. Also try to recall if there’s anything that you can think of that may cause this such as switching the diet to a food that has lower calories, increasing the exercise or not feeding as much. If there are multiple people feeding Skye, it’s possible that someone is not feeding as much.
I hope this is helpful and please feel free to post any additional questions.
1Pet Parents found this answer helpful

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