Sebaceous Cyst or Blackhead? What to Know

A blackhead is a small open comedone formed when oil and dead skin block a pore. An epidermoid cyst, often called a sebaceous cyst, is a closed pocket lined with skin cells and filled with keratin. The cyst may feel like a rounded lump under the surface, while a blackhead is usually a more superficial spot. A cyst can present with a punctum, which is the visible dark opening that causes confusion between the two.

Size, depth, tenderness, recurrence, and the material released are clues, but squeezing the area cannot reliably identify it.

Leave the spot alone rather than trying to empty it with nails, pins, or repeated pressure. Gentle cleansing is reasonable, but harsh scrubbing can inflame the surrounding skin. If the lump is recurrent, enlarging, or bothersome, a dermatologist can assess it. Treatment may involve calming inflammation, draining an abscess when one is present, or removing the cyst and its sac when appropriate; these approaches are not the same as routine blackhead care.

Arrange an assessment if the area becomes painful, warm, red, swollen, or starts draining pus. Seek urgent care when redness spreads quickly, you develop fever or feel unwell, or swelling affects the eye, mouth, or breathing. A lump that repeatedly returns after it seems to empty, bleeds, or changes in appearance should also be checked.

Ask whether the dark point is a punctum or an open pore, whether the lump is inflamed, and which treatment would address its cause. Ask how to care for the site after any procedure and what recurrence would mean.