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My kitten stopped eating and playing after deworming. What's wrong?

Updated on September 23rd, 2025

Pet's info: Cat | Mixed Breed | Female | unspayed | 1.5 lbs

My 8 weeks kitten lose her appetite and play drive after deworming it's been 3 3days now and she didn't eat much at all.

3 Answers

Most Helpful Answer

Answered By Jessica Desrosiers

Veterinary Technician

Published on April 15th, 2021

Some loss of appetite/lethargy can be normal after a deworming, especially if there was a heavy worm load that is now dying off. You can try to entice eating by offering some plain boiled chicken or wet food warmed up as cat's appetites are driven by smell. However, if it's been several days and Layla still isn't back to normal, isn't eating or drinking at all, or is very lethargic, it is best to let your vet know to make sure there isn't another underlying issue that needs to be addressed.

10Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Dr. Dayna, DVM, CVA
Veterinarian, Certified Veterinary Acupuncturist
Published on October 13th, 2017
Deworming doesn’t usually cause cats to feel bad. If your kitty still acts sick tomorrow or won’t eat then I would recommend that she be seen by a veterinarian. Good luck and I hope she improves quickly. Thank you for using Pet Coach.
1Pet Parents found this answer helpful
Answered By Ana M, DVM
Veterinarian
Published on October 14th, 2020
Thank you for submitting your question regarding Penny. I recommend that she sees a veterinarian today. I worry that she will become dehydrated from not eating well and losing fluid in the diarrhea. The veterinarian will examine her and determine if she would benefit from fluids under her skin and possibly anti-nausea medication. Deworming medication can make a kitten sick if she had a high worm burden. As the parasites die off, the kitten can become ill. I hope this information helps!
1Pet Parents found this answer helpful

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Related Questions

My 3-month-old kitten suddenly won't eat after deworming. Help!

Hi and thanks for using Petco Pet Education Center, formerly Petcoach! Sorry to hear about Laila. I would advise taking her to your vet immediately if she won't eat. She may be running a fever, have some pain/discomfort, etc. Your vet can take a detailed history, perform an examination, and recommend a diagnostic/treatment plan. Once a diagnosis is made a sound treatment plan can be implemented. You can try cyproheptadine if you have it but I'm concerned she may be running a fever from a viral infection, not sure how much the cypro will help. The normal dose is 2 mg every 12 hours in cats. Good luck

Updated on September 23rd, 2025

Training & Behavior

My kitten is suddenly not playing and eating a lot. What's wrong?

Hello and thank you for contacting Petco Pet Education Center, formerly Petcoach. Lethargy and low energy level in such a young kitten is always a concern. This behaviour could be due to fever, pain, intestinal worms and more. Please de-worm your kittens if they have not been dewormed in the last few days. If it does not make any difference, please take him to your local vets for an appointment.

Updated on September 23rd, 2025

Why is my kitten not eating and hunching after dewormer shot?

It is possible that the worms were the reason why he wasn't eating, and the deworming treatment itself can make him feel nauseous and unwell. It's the result of the dead worms moving through his GI system. I would recommend offering him a bland diet of boiled white meat chicken (no bones) in small amounts to try to tempt him to eat. You can also soak his dry food in tuna juice, or offer him gently warmed really smelly wet food, such as sardine or fish based. If he still isn't eating in the morning, I would have him seen by the vet again. It will take at least two deworming treatments to kill all the worms.

Updated on September 23rd, 2025

Why is my kitten sleepy and not gaining weight after deworming?

Thanks for using Petco Pet Education Center, formerly Petcoach! Without seeing the cats, it is hard to say. I recommend taking them to the vet with a fresh stool sample to rule out other parasites. Not all deworming medications treat all intestinal parasites. If negative, I would have both cats tested for feline leukemia and FIV. These are infectious diseases that could cause poor growth. Good luck and kisses to the kittens!

Updated on September 23rd, 2025

My kitten is tired after shots and deworming. Is this normal?

I am concerned as well. While a kitten can have some lethargy after receiving vaccines and deworming treatments, it's not normal for that to last more than a day or two. If she is eating and drinking normally, then you can wait until the morning to have her seen by a vet by a health check. Should she not be eating or drinking normally, then I would have her seen by an ER vet tonight.

Updated on September 23rd, 2025

Health & Wellness

Why is my kitten vomiting yellow and not eating after dewormer?

Thank you for submitting your question regarding your kitten. If he is not improving, then I recommend that he has a further work up. He should have fecal testing, blood work and x-rays of his abdomen to determine the cause of his vomiting and inappetance. Kittens can react to deworming medication, but it is typically a short lived reaction. It worries me that he is still ill. There is likely another another disease process present. In the meantime, encourage him to drink so that he does not become dehydrated. I hope this information helps!

Updated on September 23rd, 2025

Health & Wellness

My cat isn't eating after worm medicine. Is this a normal side effect?

It could be due to the death of the worms in Remy's system, as this can lead him to feel nauseous and thus decrease his eating. Try tempting him to eat by adding some boiled white meat chicken (no bones or skin) or tuna in spring water to his food. His appetite should return to normal over the next couple of days. I hope this helps!

Updated on September 23rd, 2025

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