Medically reviewed by William Truswell, MD Hair grows out of pores, small openings in the skin that secrete sweat and sebum ...

It is also a condition that can run in families. Usually sebaceous cysts aren't harmful, but occasionally they can become infected (which makes them sore ). They can also look unsightly ...

They aren't harmful and can usually be managed at home. But if a cyst gets infected, a healthcare provider may need to drain the cyst or prescribe an antibiotic to clear up the infection.

A cyst from an ingrown hair can range from a small, painless lump to a large, infected growth. Read on to learn more about ingrown hair cysts, including what causes them, how to identify them ...