Sounds like it could be a keloid. Keloids are benign so if it is one it's nothing to worry about really. They are quite common with cartilage piercings as they are an overgrowth of tissue which appears at the site of a wound. I had one one on a cartilage piercing once, a friend of mine explained what it was to me. She told me that generally they don't go away and most don't really grow big. Upon hearing that, I worried and took out my cartilage piercing and within a couple of months it was gone. I now have a little bit of scarring but that's obviously to be expected.
Welcome to the MedHelp forum!
Yes, if you have pierced the anti-tragus then it can be a keloid. It can also be a cartilage tumor either benign (Chondroma) or malignant (chondrosarcoma). Since it is red, it can also be a boil. Please consult a doctor for further examination.
It is difficult to comment beyond this at this stage. Take care!
Thanks to you both for your comments. I've never pierced the anti-tragus -- or anything but my little lobes!
Doctor Nee, what kind of doctor should I consult about this (besides my GP)? (Will it necessarily grow larger? Might it go away on its own?)
Maddie, thanks for sharing your story and congrats on your success!
A dermatologist should be the first choice.