What is this under her chin?

I found this under the cat's chin last night... what could it possibly be??? I feel so bad I hadn't seen it sooner, but with her long hair sometimes it's hard to see as her hair covered it when it wasn't viewed at the right angle.

I plan to take her into the vet tomorrow... but is there something I can do?

We adopted her a month ago. She was already 4 paws declawed and I doubt she could lick herself there, so it must be from scratching (and I doubt the other cat we have adopted 2 weeks prior this cat's adoption caused the harm).

She hasn't lost her appetite but her stool has been soft - she had a cold and then was on antibiotic...

I didn't resize the photos so you can see them in full size, so I'll post the links instead of inserting them here.

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First of all, I'm glad you're already planning on a trip to the vet. My girl gets something similar to this when she's stressed out. It starts out kind of like feline acne, but then goes into this. So, it could be feline acne, or it could be what's called a rodent ulcer, those are usually seen on the mouth. Do you only see the one or are there others?

It could also be a sore caused from playing rough with one of the other kitties - an accidental bite or scratch. And like you said, she can't exactly groom under her chin.

Please update with what the vet says. I bet, though, you'll just be told to clean it up and maybe sent home with a week of antibiotics and told to come back if it doesn't get better. Something simple.

It looks like an abcess to me. Spooky got them on her chin from food allergies. Antibiotic cleared them up temorarily, but for her the cure came with a change in diet.

Your vet will be able to figure out what it is, and the proper treatment. Good luck!

Thanks all. We went to the vet today, and he thinks this is just an isolated case. Actually today the redness was gone and it was just a slight pale pink color so it's already healing (I'd shown the pictures to the vet so he knew it was red before). He doesn't think it's contagious and thinks hair is already starting to grow back. He said just to keep an eye on it for now and take her back if it gets worse (or happens again). Otherwise she is in really good health from her physical exam. She wasn't even that nervous at the vet (first time there since we got her), she was exploring the room and ate up all the treats they gave her! This is the first time she is in contact with strangers since we'd gotten her and she did so well, she let everyone pet her!

Glad she's on the mend and had a good check-up!

Thanks stephanietx!