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Cat's vaccine reaction returned. Is it the vaccine or something else?

Updated On September 23rd, 2025

Pet's info: Cat | Persian | Female | unspayed | 4 months and 22 days old | 5 lbs

Hello My cat started to have a 103 fever like 3 days ago then the vet told me she had an allergic reaction to the vaccine booster felV and shee got iv fluids and antihistamines diphenhydramine then she was back to normal that afternoon then a day after she was normal playing and eating but then when I stopped giving her the benadryl pill because her treament ended she started to feel like this again was she very allergic to that vaccine or is she allergic to something else? s

1 Answer

Most Helpful Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on March 30th, 2020

Thank you for contacting Petco Pet Education Center, formerly Petcoach with your question about Arion. Poor girl! It could be an allergy to something else or she may need a stronger medication like steroids to treat the initial allergic reaction. Sometimes antihistamines are not enough to control the reaction. I would have her seen by a vet again now if her symptoms have returned to get additional medication. I hope this helps!

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