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My cat's neck lump broke open and spread. Is it healing or worsening?

Updated On September 23rd, 2025

Pet's info: Cat | Mixed Breed | Male | neutered | 5 lbs

my cat developed a lump under the skin on the back of the neck....a day or two later it festered and broke open. I applied hydrogen peroxide to the area but it spread rapidly into a series of sores and the hair fell out...I applied a topical antibiotic ointment and gave her small doses of oral antibioyic....it cleared most of it up but there are still bumps under the skin on the rim of the original site... I can not tell if it is under control or getting ready to spread outward.

1 Answer

Most Helpful Answer

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Answered By Jennifer Summerfield, DVM CPDT-KA

Veterinarian, Certified Dog Trainer

Published on July 9th, 2017

Poor Munchkin! I'm sorry to hear that he's having this problem. Without being able to examine him, or at least see a photo of the area, it's hard to say what this might be and whether it is healing appropriately or not. From your description, it sounds like it could be a ruptured cyst or skin tumor of some kind, or possibly a rather nasty localized infection. It sounds like you have been doing a good job of keeping the area clean. I wouldn't consider this problem to be urgent as long as he is acting normal otherwise, but I would recommend taking Munchkin to your regular vet tomorrow to have this checked. He/she can examine the area to determine if additional treatment is needed, to make sure that it heals without further problems.

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