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My senior cat reacted to flea treatment with skin issues. Why?

Updated On September 23rd, 2025

Pet's info: Cat | Domestic Longhair | Male | neutered

Hi I am worried about my cat gangsta. Although I am taking him to the vet tomorrow. He is 18 next month. I have given him broadband for fleas and worms before but I hadn't given him any for a while. Well I gave him some three days ago and he reacted badly for the very first time ever. I used to give him regular treatment. I think he has a flea allergy?? I'm sure that's what the vet said before?? Also eczema?? He has scratched the area that was done with the flea treatment red raw with bald patch

1 Answer

Most Helpful Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on November 17th, 2019

Poor Jack. If cats have a heavy burden of fleas, yes they can get a flea allergy. I'm concerned that he reacted badly to the flea medication, but I don't know what reaction he had. I think it's best to take him into his vet today.

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