What should you know about cysts on scalp under hair?

A pilar cyst, also called a trichilemmal cyst, develops around a hair follicle and commonly feels like a smooth, rounded lump in the scalp. Hair can make it difficult to see the surface, so you may first notice it while washing, brushing, or lying down. Some scalp cysts remain quiet and firm.

Friction from combs, helmets, or sleeping can make a cyst sore. Inflammation may cause tenderness, redness, warmth, swelling, or drainage. A scalp lump is not automatically a cyst; its size, depth, attachment, and changes over time help a clinician decide what it is.

Use gentle hair care and avoid picking, squeezing, or repeatedly checking the lump with pressure. Ask someone to look at the skin if hair obscures it, and note its position and any change in pain, size, colour, or drainage. Do not try to cut or pierce it, since the scalp can bleed and an opening can become infected.

A small, comfortable cyst may be monitored. If it catches on grooming tools, recurs, or causes discomfort, a clinician may discuss cyst removal. The plan depends on the lump and the condition of the surrounding scalp.

Arrange a dermatology review for a new or persistent scalp lump, especially if it grows, becomes fixed, repeatedly swells, or affects nearby hair or skin. Seek prompt care for spreading redness, heat, severe pain, pus-like drainage, fever, or feeling unwell. A sudden change should be checked rather than attributed to friction.

Does this feel like a pilar cyst or another scalp lump? Can it be safely watched? If removal is advised, how will the hair and wound be managed, and what changes should prompt earlier review?