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

A skin cyst can feel round, smooth, or firm and may move slightly beneath the surface. Some have a tiny central opening, while others are covered by normal-looking skin. The contents are usually trapped skin cells and keratin. A cyst is different from an abscess, which is an infected pocket that is more likely to be hot, painful, swollen, or draining. A new or changing lump can have other causes, so appearance alone cannot confirm the diagnosis. Learn more about [Skin Lumps](/symptoms/skin-lumps/).

Do not squeeze, pierce, or repeatedly massage the area; this can irritate the wall and introduce infection. Keep the skin clean and note its size, tenderness, colour, and whether it leaks. A clinician can examine it and discuss observation, a steroid injection for selected inflammation, drainage when infection is present, or [Cyst Removal](/treatments/surgical-dermatology/cyst-removal/) when the whole cyst needs treatment. [Abscess Drainage](/treatments/minor-procedures/abscess-drainage/) is a different procedure from removing a cyst wall.

Arrange a medical assessment if the lump grows, becomes painful, turns red or hot, opens, drains, or keeps returning. Seek prompt care for spreading redness, fever, marked swelling, or pain that is rapidly worsening. A lump that is hard, fixed, bleeding, or changing in colour also deserves an examination rather than home treatment.

Ask: Does this look like a cyst or another type of lump? Is observation reasonable? What changes should prompt a review? If treatment is considered, would injection, drainage, or removal address the cause?