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My puppy is lethargic and not eating after vaccine. Is this normal?

Updated on September 23rd, 2025

Pet's info: Dog | Boxer | Female | unspayed | 3 months and 17 days old | 22 lbs

My 3.5 month old female boxer received her rabies vaccine today. She was also microchipped at her appointment. She has not really eaten a thing or drank water. She is very lethargic and just isn't herself. Is this a normal reaction?

2 Answers

Most Helpful Answer

Answered By Cara, DVM, cVMA

Veterinarian

Published on August 8th, 2017

I'm sorry Milli isn't feeling well! It's relatively common for dogs to feel lethargic or sore after vaccines. It usually resolves on its own within 24 hours. If she has any vomiting, diarrhea, facial swelling or hives I would take her to the vet right away. Otherwise, make sure she has access to water but I'd call your vet tomorrow if she's not back to normal by then.

1Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By David Darvishian
Veterinarian
Hi and thanks for using Petco Pet Education Center, formerly Petcoach! Sorry to hear about Milli. The after effects from vaccines are usually mild and self limiting but sometimes we see a lot of discomfort/pain at the injection site, reluctance to move, fever, decreased appetite and possibly decreased water intake. Some reactions are even more severe including facial swelling, vomiting, diarrhea, and even collapse. I would watch her very closely and if her signs progress or new signs develop, I would have her evaluated as soon as you can. I would try to tempt her with some canned food and you can even warm it slightly in the microwave to enhance the aroma. Just make sure to test the temperature of the food before offering it to her. You can also try some chicken broth in her water to see if she will drink some of that. The next 12-24 hours will hopefully go better and she will start returning to normal. Problems with microchips are very rare at least from what I have seen. If she is not better soon or by morning, I would at least call your veterinarian and see if they want to look at her and evaluate whether she needs something to ease her pain or ease her fever if she has one. Good luck with Milli
1Pet Parents found this answer helpful

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