What should you know about an infected sebaceous cyst on the head?

A cyst is a sac beneath the skin that can contain keratin and may have a small opening at its surface. When inflamed or infected, it can enlarge, feel hot and sore, redden the surrounding scalp, and release thick or foul-smelling material. Pressure from sleeping, hats, helmets, or hair tools can make discomfort worse. A cyst can resemble another type of skin lump, so examination is useful when it is new, changing, recurrent, or firmly attached.

Keep the area clean and avoid pressing, squeezing, or trying to pierce it. Use a clean dressing if fluid is draining, and wash your hands after touching the site. A warm compress may soothe discomfort, but stop if swelling or pain increases. A clinician may recommend abscess drainage when infected fluid has collected. Once inflammation settles, cyst removal can reduce the chance of repeated episodes; steroid injection into the skin may be considered for selected inflammation but does not remove the cyst wall.

Arrange prompt care if the lump is growing quickly, very painful, draining pus, or surrounded by spreading redness. Seek urgent help for fever, severe headache with feeling unwell, confusion, faintness, red streaks, swelling near the eye, or difficulty opening the eye. Do not delay review if the cyst keeps returning or the scalp wound does not heal.

Ask whether this is an infected cyst or an abscess, whether drainage is needed, how to protect the scalp while it heals, and when complete cyst removal should be considered. Mention previous episodes, drainage colour and smell, fever, and any medicines that affect healing.