Overlarge pore/cyst? on arm

I noticed a few months back that a pore on my arm had become a bit larger than normal, and that the skin was raised underneath. When pressed, it was mildly painful and I felt a hard mass underneath. A little alarmed, I started hot/cold compresses to bring it to a head, thinking it was simply an overlarge pimple. It took me about two days, but i finally was able to expell the mass via tightening the skin around my arm and squeezing around the pore. A large amount of pus came out, along with a bit of relief from the pain, but now it keeps filling up, and the pore refuses to shrink. Is it a cyst on my arm, or simply just an overlarge pimple? Either way, is the constant refilling of the pus chamber cause for concern and should I see a dermatologist?

[maatson]

Perhaps an infected 'sebaceous cyst'. Can easily be removed if so.

[Bhupinder Kaur, MD]

Hello,
It can be a sebaceous cyst. A sebaceous cyst is a closed sac occurring just under the skin which contains a "pasty" or "cheesy" looking substance called keratin.They may occur anywhere on body but scalp, ears, back, face, and upper arm, are common sites for sebaceous cysts. Blocked sebaceous glands, swollen hair follicles and excessive testosterone production will cause such cysts.

Generally no treatment is required but they become painful then it means they are infected,Then surgical excision by traditional wide excision, minimal excision, and punch biopsy excision may be required.
I hope it helps. Take care and regards.