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My cat's losing armpit hair, has a sore head, and a lump. Help!

Updated On September 23rd, 2025

Pet's info: Cat | Mixed Breed | Female | 7 years and 8 months old | 12 lbs

hi my cat bella age 7 no breed has lost all hair ander both of her armpits she has a sore head but seems fine he found a lump of her hair we dont know if she is ok thanks charlotte.

1 Answer

Most Helpful Answer

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Answered By David Elbeze, DVM, MRCVS

Veterinarian

Published on January 8th, 2017

This is probably caused by an allergic reaction. first of all make sure you flea your cat regularly every month with a high quality spot on (ex. Advantage) as fleas are by far the most common reason for these reactions. If the fleas are not the problem, it could be an allergic reaction to food or an environmental factor. this is more complicated to treat and will sometimes require medications such as Steroids, anti histamines or cyclosporin in order to stop the allergy. Regarding the lump, it needs to be checked to make sure it's not a tumor, usually a simple FNA test can give some answers regarding the nature of the lump.

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