Petco Text Logo
Petco Pet Logo
  • Two Easy Ways to Start Earning Rewards!

    rewards header
    Become a member today!
    Members-only pricing and offers, personalized care notifications, Vital Care points back on every purchase and more!
    Petco Pay LogoBecome a credit card member today!

    Earn 2X Pals Rewards points at Petco
    when you use Petco Pay!

    APPLY NOW
    Learn More About Petco Pay Benefits

My cat is vomiting, lethargic, and not eating on antibiotics.

Updated on September 23rd, 2025

Pet's info: Cat | Domestic Shorthair | Male | neutered | 11 lbs

My cat was prescribed antibiotics for diarrhea and today was his second day of taking them. He’s required to take 0.5 mL of the antibiotic and another one after 12 hours (twice a day). Today, he lost his appetite (only ate a few treats) and threw up clear liquid twice and clear yellow liquid 3 times. He is also lethargic.

1 Answer

Most Helpful Answer

Dr. Strydom, DVM

Answered By Dr. Strydom, DVM

Veterinarian

Published on April 29th, 2024

Hello, thank you for using Petco Pet Education Center, formerly Petcoach. I'm sorry to hear that Leo is having this problem.

Many antibiotics cause gastrointestinal issues in cats so you will need to call your vet and let them know what is going on. Most likely they will have you stop one or both of the antibiotics and prescribe something different.

I would also suggest that you put him on a pre/probiotic while he is taking antibiotics and then continue for at least one week after the antibiotics have been stopped.

Hope this helps. Best wishes.
Vote Icon1Pet Parents found this answer helpful

Smart Picks for Smart Questions

Have A Vet Question?

Book an appointment with the pros – our expert vets are here to help.

Share

Styled arrow button