What should you know about a cyst over the scalp?

Pilar cysts, also called trichilemmal cysts, commonly develop on the scalp. They can feel firm or rubbery, sit beneath the skin, and move slightly when touched. Some remain small and quiet, while others gradually become more noticeable or catch on a comb.

A lump cannot be identified reliably from appearance alone. A clinician may examine its surface, depth, tenderness, and attachment to nearby tissue. A painful, warm, or reddened lump can reflect inflammation or infection; a sudden change deserves medical review rather than home treatment.

Do not squeeze, pierce, or cut the lump. These actions can irritate the skin, introduce bacteria, and leave the cyst wall behind, allowing the lump to return. Keep the area clean and take care while brushing or styling your hair.

Arrange a dermatology appointment if the lump is persistent, enlarging, repeatedly irritated, or interfering with sleep, grooming, or wearing head coverings. If removal is appropriate, a clinician can discuss a procedure designed to take out the cyst and its capsule; the choice depends on its condition and location.

Seek prompt medical advice if the scalp becomes increasingly red, hot, swollen, or tender, or if fluid with an unpleasant smell drains from the lump. Fever, spreading redness, or feeling generally unwell can signal an infection that needs treatment.

Get urgent help for rapidly worsening swelling, severe pain, or swelling near the eye or face. Do not delay assessment after an injury if the lump changes quickly or bleeding does not settle with gentle pressure.

You could ask: Does this look like a pilar cyst or another type of scalp lump? What changes should prompt a faster review? If removal is advised, will the cyst be examined after the procedure, and how should the wound be cared for while it heals?