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Why is my dog lethargic and shaking after getting his shots today?

Updated on September 23rd, 2025

Pet's info: Dog | Mixed Breed Large (61lb +) | Male | 1 year and 9 months old | 70 lbs

Pitbull got Imrab 3 TF and DApp today. He is lethargic and shaking like he is cold. Should I be worried?

3 Answers

Most Helpful Answer

Answered By Ricardo Fernandez, DVM

Veterinarian, Veterinary Oncology Resident

Published on February 5th, 2018

Thanks for using Petco Pet Education Center, formerly Petcoach! Possible side effects after vaccines include pain at the injection site, lethargy, inappetence and general discomfort. This should subside within 1-2 days. If it does not improve or it worsens, have Boomer evaluated by a veterinarian for further assessment and treatment. Otherwise, Boomer will likely start feeling better shortly. Good luck and best wishes!

1Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Angel Alvarado, LVT
Licensed Veterinary Technician
Published on February 28th, 2019
This can happen after vaccines. If it lasts longer than 24 hours, have her rechecked by your veterinarian. Monitor for vomiting, diarrhea, difficulty breathing or any swelling. These can indicate a vaccine reaction and should be addressed immediately by your veterinarian or at the nearest veterinary ER.
1Pet Parents found this answer helpful
Answered By Ricardo Fernandez, DVM
Veterinarian, Veterinary Oncology Resident
Published on July 1st, 2019
Thanks for using Petco Pet Education Center, formerly Petcoach! Possible side effects after vaccines include pain at the injection site, lethargy, inappetence and general discomfort. This should subside within 1-2 days. If it does not improve or it worsens, have Missy evaluated by a veterinarian for further assessment and treatment. Otherwise, Missy will likely start feeling better shortly. Good luck and best wishes!
1Pet Parents found this answer helpful

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