Cyst on the Skull Under the Skin: What to Know

A skin cyst can feel like a smooth, rounded lump beneath the scalp and may move slightly over the tissue. It can remain quiet for a long time, become tender after irritation, or develop redness and warmth if inflamed. A cyst is different from a swollen lymph node, a benign fatty lump, or another scalp growth, so appearance alone cannot confirm the diagnosis. Do not assume that a lump is a cyst simply because it feels familiar.

Avoid squeezing, piercing, or cutting it at home. These actions can push material deeper, introduce bacteria, and make later removal more difficult. Gentle washing is reasonable while you arrange an assessment.

Arrange a routine dermatology or primary-care visit for a lump that persists, enlarges, catches on clothing or hair tools, or repeatedly becomes sore. The clinician may inspect and feel the lesion and discuss observation, an injection for selected inflammation, drainage when infection is present, or removal of the cyst wall when recurrence is a concern. Learn more about [Skin Lumps](/symptoms/skin-lumps/) and [Cyst Removal](/treatments/surgical-dermatology/cyst-removal/).

Seek prompt medical advice if the scalp becomes increasingly painful, red, hot, swollen, or starts draining thick or foul-smelling fluid. Fever, rapidly spreading redness, or feeling unwell can signal an infection needing assessment. Urgent review is also sensible for a lump that grows quickly, bleeds without an obvious injury, feels fixed, or causes new numbness or weakness. Do not delay care while waiting for it to settle if these changes appear.

Ask: Does this look like a cyst or another scalp lump? Is observation appropriate? What signs would suggest infection? If treatment is needed, would [Steroid Injection Into The Skin](/treatments/injectables/intralesional-steroid-injection/) or [Abscess Drainage](/treatments/minor-procedures/abscess-drainage/) fit the findings? How can recurrence be reduced?