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My kitten is sick and won't eat after vaccinations. What to do?

Updated on September 23rd, 2025

Pet's info: Cat | Persian | Female | unspayed | 3 months and 6 days old

Yesterday i gave my 3 months old cat lily shots for rabies and feline panleukopenia...today she is lethargic, has fever, isnt eating or drinking and neither pooping...what should i do? I at least want her to eat

4 Answers

Most Helpful Answer

Answered By Laura Johnson VMD

Veterinarian

Published on September 14th, 2017

Hi, thanks for using Petco Pet Education Center, formerly Petcoach! Poor Lily!

Lily is likely having a reaction to the vaccines. If she has a fever she needs to see a veterinarian. When animals have fevers they do not want to eat. Your Vet, after their exam, will likely give her subcutaneous fluids and steroids. Once the fever and the reaction has subsided Lily will likely eat. There is nothing to do at home besides wait out the fever and that may take to long. Cats can not go more than 3 days with out eating or they get sicker.

I hope this helps and I wish you and Lily the best!

1Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Rodrigo Roca, DVM
Veterinarian
Published on January 17th, 2018
Hello, sorry to hear about Rose. Pets as do humans may experience lethargy, occasionally pain, heat or swelling at the site of injection after they have received a vaccines. Signs may last up to 3 days and are typically self limiting. More severe vaccine reactions include vomiting, decreased appetite, fever, hives, or facial swelling and these should be evaluated by a veterinarian immediately.

If Rose is not feeling better in 1-2 days, have her evaluated by her veterinarian. Hope this helps and best of luck.
1Pet Parents found this answer helpful
Answered By Mirissa Duncil, DVM
Veterinarian
Published on September 18th, 2017
Hi and thanks for using Petco Pet Education Center, formerly Petcoach!

This sounds like a reaction to the vaccines she received yesterday. While some tiredness and soreness (which can manifest as lameness) can be expected (as well as a bit of decreased appetite), any extremes of any of these, or if they last for more than 24 hours- you should call your veterinarian asap to alert them that she has had a vaccination reaction. Likely they will have you bring her in for a quick re-examination and treatment if it is warranted (sometimes a steroid injection will be give to counteract the vaccine's effect).

I hope this helps and that Sugar feels better soon!
1Pet Parents found this answer helpful
Answered By David Elbeze, DVM, MRCVS
Veterinarian
Published on July 8th, 2017
It seems as she is suffering from nausea, that could be due to a gastrointestinal condition and i'm not sure it's related to the vaccination. if she is not better by tomorrow- take her to the vet in order to get her checked and treated.
1Pet Parents found this answer helpful

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