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 scratching and unsettled after flea medicine. Is it normal?

Updated on September 23rd, 2025

Hi I have just given my cat Johnson's flea tablet he has had these before but it excessively scratching this time and very unsettled unsure what to do

2 Answers

Most Helpful Answer

Debi Matlack

Answered By Debi Matlack

Veterinary Technician

Published on July 4th, 2015

Johnson's flea tablet sound very much like a product I am familiar with called Capstar. It is meant to kill the fleas on the pet right away and to be used in conjunction with a longer acting flea product. It's helpful because it starts working quickly, but the effects only last for 24 hours. Your cat may be unsettled because she has a decent flea population on her and now the dying fleas as running around and making her itch. As long as she is okay otherwise, eating, drinking, eliminating normally, with no adverse symptoms such as vomiting, diarrhea, lethargy or loss of appetite, I'm inclined to believe that this is what is happening. If she develops any of these symptoms, get her seen by you vet right away.
Vote Icon7Pet Parents found this answer helpful

Related Answers from Veterinarians

  • Answered By Dr. Strydom, DVM

    Veterinarian

    Published on March 21st, 2020

    Yes, I would be a bit concerned. Unfortunately, not all medications work well on an animals. I would consider this an abnormal reaction. I suggest you wash her with some Dawn Dish Soap to remove all the residual product from her body.

    If she stops eating or using the bathroom she needs to see a vet ASAP. I recommend you use a different product on her from now on. Maybe a Seresto collar?

    https://www.petco.com/shop/en/petcostore/product/seresto-flea-and-tick-collar-for-cats

    Vote Icon

    1Pet 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