What should you know about a large cyst under the skin?

An epidermoid cyst can feel round, smooth, and mobile beneath the skin. It may have a small central opening and can remain quiet for a long time. A cyst is different from an abscess, although it can become inflamed or infected and then feel tender, warm, swollen, or red. Other types of skin lumps can look similar, so appearance alone cannot confirm the diagnosis.

Do not squeeze, puncture, or try to empty it at home. Pressure can push material deeper, irritate the surrounding skin, and make infection harder to manage. A clinician may examine its depth, contents, and connection with nearby tissue.

Arrange a dermatology or primary-care assessment if the lump is large, repeatedly returns, catches on clothing, or interferes with movement. Keep the area clean and avoid rubbing it. A warm, moist compress may ease discomfort when the skin is closed, but stop if pain or redness increases.

Treatment depends on whether the cyst is calm, inflamed, or infected. A steroid injection into the skin may reduce inflammation in selected cases. An abscess may need drainage, while cyst removal can take out the cyst wall and reduce recurrence. These are different procedures and are chosen after examination.

Seek prompt medical advice if the lump becomes rapidly larger, hot, very painful, increasingly red, or starts draining thick or foul-smelling fluid. Fever, red streaking, or feeling generally unwell can signal a spreading infection and needs urgent assessment. A hard, fixed, bleeding, or persistently changing lump also deserves examination rather than home treatment.

Ask whether the lump appears to be an epidermoid cyst or another type of skin lump, whether inflammation or infection is present, and whether removal should wait until swelling settles. You can also ask about scarring, recurrence, wound care, and what changes should trigger a follow-up visit.